diff --git a/src/common/src/tdataformat.c b/src/common/src/tdataformat.c
index 719d80aa775bf3b5abe3065ef7eca799d452e315..12ea4ad78d18a5f2b09daabb71093c153d30aca7 100644
--- a/src/common/src/tdataformat.c
+++ b/src/common/src/tdataformat.c
@@ -318,7 +318,7 @@ SDataCols *tdNewDataCols(int maxRowSize, int maxCols, int maxRows) {
   pCols->maxPoints = maxRows;
   pCols->bufSize = maxRowSize * maxRows;
 
-  pCols->buf = calloc(1, pCols->bufSize);
+  pCols->buf = malloc(pCols->bufSize);
   if (pCols->buf == NULL) {
     free(pCols);
     return NULL;
diff --git a/src/tsdb/inc/tsdbMain.h b/src/tsdb/inc/tsdbMain.h
index 210d95853cf216e93dd09feb4f8e03e15b269471..762d2253e21aca6c95318cdbcda16a31da9b45cf 100644
--- a/src/tsdb/inc/tsdbMain.h
+++ b/src/tsdb/inc/tsdbMain.h
@@ -42,6 +42,7 @@ extern int tsdbDebugFlag;
 #define TSDB_MAX_TABLE_SCHEMAS 16
 #define TSDB_FILE_HEAD_SIZE 512
 #define TSDB_FILE_DELIMITER 0xF00AFA0F
+#define TSDB_FILE_INIT_MAGIC 0xFFFFFFFF
 
 // Definitions
 // ------------------ tsdbMeta.c
@@ -132,21 +133,30 @@ typedef struct {
 // ------------------ tsdbFile.c
 extern const char* tsdbFileSuffix[];
 typedef enum {
+#ifdef TSDB_IDX
+  TSDB_FILE_TYPE_IDX = 0,
+  TSDB_FILE_TYPE_HEAD,
+#else
   TSDB_FILE_TYPE_HEAD = 0,
+#endif
   TSDB_FILE_TYPE_DATA,
   TSDB_FILE_TYPE_LAST,
   TSDB_FILE_TYPE_MAX,
+#ifdef TSDB_IDX
+  TSDB_FILE_TYPE_NIDX,
+#endif
   TSDB_FILE_TYPE_NHEAD,
   TSDB_FILE_TYPE_NLAST
 } TSDB_FILE_TYPE;
 
 typedef struct {
-  uint32_t offset;
+  uint32_t magic;
   uint32_t len;
-  uint64_t size;      // total size of the file
-  uint64_t tombSize;  // unused file size
   uint32_t totalBlocks;
   uint32_t totalSubBlocks;
+  uint32_t offset;
+  uint64_t size;      // total size of the file
+  uint64_t tombSize;  // unused file size
 } STsdbFileInfo;
 
 typedef struct {
@@ -197,6 +207,7 @@ typedef struct {
 
 // ------------------ tsdbRWHelper.c
 typedef struct {
+  int32_t  tid;
   uint32_t len;
   uint32_t offset;
   uint32_t hasLast : 2;
@@ -220,7 +231,7 @@ typedef struct {
 
 typedef struct {
   int32_t    delimiter;  // For recovery usage
-  int32_t    checksum;   // TODO: decide if checksum logic in this file or make it one API
+  int32_t    tid;
   uint64_t   uid;
   SCompBlock blocks[];
 } SCompInfo;
@@ -249,24 +260,27 @@ typedef struct {
 typedef enum { TSDB_WRITE_HELPER, TSDB_READ_HELPER } tsdb_rw_helper_t;
 
 typedef struct {
-  int   fid;
-  TSKEY minKey;
-  TSKEY maxKey;
-  // For read/write purpose
-  SFile headF;
-  SFile dataF;
-  SFile lastF;
-  // For write purpose only
-  SFile nHeadF;
-  SFile nLastF;
+  TSKEY      minKey;
+  TSKEY      maxKey;
+  SFileGroup fGroup;
+#ifdef TSDB_IDX
+  SFile nIdxF;
+#endif
+  SFile      nHeadF;
+  SFile      nLastF;
 } SHelperFile;
 
 typedef struct {
   uint64_t uid;
   int32_t  tid;
-  int32_t  sversion;
 } SHelperTable;
 
+typedef struct {
+  SCompIdx* pIdxArray;
+  int       numOfIdx;
+  int       curIdx;
+} SIdxH;
+
 typedef struct {
   tsdb_rw_helper_t type;
 
@@ -274,7 +288,9 @@ typedef struct {
   int8_t     state;
   // For file set usage
   SHelperFile files;
-  SCompIdx*   pCompIdx;
+  SIdxH       idxH;
+  SCompIdx    curCompIdx;
+  void*       pWIdx;
   // For table set usage
   SHelperTable tableInfo;
   SCompInfo*   pCompInfo;
@@ -286,7 +302,6 @@ typedef struct {
   void*      compBuffer;  // Buffer for temperary compress/decompress purpose
 } SRWHelper;
 
-
 // Operations
 // ------------------ tsdbMeta.c
 #define TABLE_TYPE(t) (t)->type
@@ -296,6 +311,7 @@ typedef struct {
 #define TABLE_TID(t) (t)->tableId.tid
 #define TABLE_SUID(t) (t)->suid
 #define TABLE_LASTKEY(t) (t)->lastKey
+#define TSDB_META_FILE_MAGIC(m) KVSTORE_MAGIC((m)->pStore)
 
 STsdbMeta* tsdbNewMeta(STsdbCfg* pCfg);
 void       tsdbFreeMeta(STsdbMeta* pMeta);
@@ -445,6 +461,16 @@ void        tsdbGetFidKeyRange(int daysPerFile, int8_t precision, int fileId, TS
 #define helperRepo(h) (h)->pRepo
 #define helperState(h) (h)->state
 #define TSDB_NLAST_FILE_OPENED(h) ((h)->files.nLastF.fd > 0)
+#define helperFileId(h) ((h)->files.fGroup.fileId)
+#ifdef TSDB_IDX
+#define helperIdxF(h) (&((h)->files.fGroup.files[TSDB_FILE_TYPE_IDX]))
+#define helperNewIdxF(h) (&((h)->files.nIdxF))
+#endif
+#define helperHeadF(h) (&((h)->files.fGroup.files[TSDB_FILE_TYPE_HEAD]))
+#define helperDataF(h) (&((h)->files.fGroup.files[TSDB_FILE_TYPE_DATA]))
+#define helperLastF(h) (&((h)->files.fGroup.files[TSDB_FILE_TYPE_LAST]))
+#define helperNewHeadF(h) (&((h)->files.nHeadF))
+#define helperNewLastF(h) (&((h)->files.nLastF))
 
 int  tsdbInitReadHelper(SRWHelper* pHelper, STsdbRepo* pRepo);
 int  tsdbInitWriteHelper(SRWHelper* pHelper, STsdbRepo* pRepo);
diff --git a/src/tsdb/src/tsdbFile.c b/src/tsdb/src/tsdbFile.c
index 95cc47292b1c24735fb564c7a6091fdeba801868..767fbc82529f401be1c25186e67af23c773cf5c7 100644
--- a/src/tsdb/src/tsdbFile.c
+++ b/src/tsdb/src/tsdbFile.c
@@ -30,7 +30,11 @@
 #include "ttime.h"
 #include "tfile.h"
 
+#ifdef TSDB_IDX
+const char *tsdbFileSuffix[] = {".idx", ".head", ".data", ".last", "", ".i", ".h", ".l"};
+#else
 const char *tsdbFileSuffix[] = {".head", ".data", ".last", "", ".h", ".l"};
+#endif
 
 static int   tsdbInitFile(SFile *pFile, STsdbRepo *pRepo, int fid, int type);
 static void  tsdbDestroyFile(SFile *pFile);
@@ -108,7 +112,7 @@ int tsdbOpenFileH(STsdbRepo *pRepo) {
 
     memset((void *)(&fileGroup), 0, sizeof(SFileGroup));
     fileGroup.fileId = fid;
-    for (int type = TSDB_FILE_TYPE_HEAD; type < TSDB_FILE_TYPE_MAX; type++) {
+    for (int type = 0; type < TSDB_FILE_TYPE_MAX; type++) {
       if (tsdbInitFile(&fileGroup.files[type], pRepo, fid, type) < 0) {
         tsdbError("vgId:%d failed to init file fid %d type %d", REPO_ID(pRepo), fid, type);
         goto _err;
@@ -126,7 +130,7 @@ int tsdbOpenFileH(STsdbRepo *pRepo) {
   return 0;
 
 _err:
-  for (int type = TSDB_FILE_TYPE_HEAD; type < TSDB_FILE_TYPE_MAX; type++) tsdbDestroyFile(&fileGroup.files[type]);
+  for (int type = 0; type < TSDB_FILE_TYPE_MAX; type++) tsdbDestroyFile(&fileGroup.files[type]);
 
   tfree(tDataDir);
   if (dir != NULL) closedir(dir);
@@ -139,7 +143,7 @@ void tsdbCloseFileH(STsdbRepo *pRepo) {
 
   for (int i = 0; i < pFileH->nFGroups; i++) {
     SFileGroup *pFGroup = pFileH->pFGroup + i;
-    for (int type = TSDB_FILE_TYPE_HEAD; type < TSDB_FILE_TYPE_MAX; type++) {
+    for (int type = 0; type < TSDB_FILE_TYPE_MAX; type++) {
       tsdbDestroyFile(&pFGroup->files[type]);
     }
   }
@@ -156,7 +160,7 @@ SFileGroup *tsdbCreateFGroupIfNeed(STsdbRepo *pRepo, char *dataDir, int fid, int
   SFileGroup *pGroup = tsdbSearchFGroup(pFileH, fid, TD_EQ);
   if (pGroup == NULL) {  // if not exists, create one
     pFGroup->fileId = fid;
-    for (int type = TSDB_FILE_TYPE_HEAD; type < TSDB_FILE_TYPE_MAX; type++) {
+    for (int type = 0; type < TSDB_FILE_TYPE_MAX; type++) {
       if (tsdbCreateFile(&pFGroup->files[type], pRepo, fid, type) < 0)
         goto _err;
     }
@@ -169,7 +173,7 @@ SFileGroup *tsdbCreateFGroupIfNeed(STsdbRepo *pRepo, char *dataDir, int fid, int
   return pGroup;
 
 _err:
-  for (int type = TSDB_FILE_TYPE_HEAD; type < TSDB_FILE_TYPE_MAX; type++) tsdbDestroyFile(&pGroup->files[type]);
+  for (int type = 0; type < TSDB_FILE_TYPE_MAX; type++) tsdbDestroyFile(&pGroup->files[type]);
   return NULL;
 }
 
@@ -260,6 +264,7 @@ int tsdbCreateFile(SFile *pFile, STsdbRepo *pRepo, int fid, int type) {
   }
 
   pFile->info.size = TSDB_FILE_HEAD_SIZE;
+  pFile->info.magic = TSDB_FILE_INIT_MAGIC;
 
   if (tsdbUpdateFileHeader(pFile, 0) < 0) {
     tsdbCloseFile(pFile);
@@ -323,23 +328,25 @@ int tsdbUpdateFileHeader(SFile *pFile, uint32_t version) {
 
 int tsdbEncodeSFileInfo(void **buf, const STsdbFileInfo *pInfo) {
   int tlen = 0;
-  tlen += taosEncodeFixedU32(buf, pInfo->offset);
+  tlen += taosEncodeFixedU32(buf, pInfo->magic);
   tlen += taosEncodeFixedU32(buf, pInfo->len);
-  tlen += taosEncodeFixedU64(buf, pInfo->size);
-  tlen += taosEncodeFixedU64(buf, pInfo->tombSize);
   tlen += taosEncodeFixedU32(buf, pInfo->totalBlocks);
   tlen += taosEncodeFixedU32(buf, pInfo->totalSubBlocks);
+  tlen += taosEncodeFixedU32(buf, pInfo->offset);
+  tlen += taosEncodeFixedU64(buf, pInfo->size);
+  tlen += taosEncodeFixedU64(buf, pInfo->tombSize);
 
   return tlen;
 }
 
 void *tsdbDecodeSFileInfo(void *buf, STsdbFileInfo *pInfo) {
-  buf = taosDecodeFixedU32(buf, &(pInfo->offset));
+  buf = taosDecodeFixedU32(buf, &(pInfo->magic));
   buf = taosDecodeFixedU32(buf, &(pInfo->len));
-  buf = taosDecodeFixedU64(buf, &(pInfo->size));
-  buf = taosDecodeFixedU64(buf, &(pInfo->tombSize));
   buf = taosDecodeFixedU32(buf, &(pInfo->totalBlocks));
   buf = taosDecodeFixedU32(buf, &(pInfo->totalSubBlocks));
+  buf = taosDecodeFixedU32(buf, &(pInfo->offset));
+  buf = taosDecodeFixedU64(buf, &(pInfo->size));
+  buf = taosDecodeFixedU64(buf, &(pInfo->tombSize));
 
   return buf;
 }
@@ -358,7 +365,7 @@ void tsdbRemoveFileGroup(STsdbRepo *pRepo, SFileGroup *pFGroup) {
   pFileH->nFGroups--;
   ASSERT(pFileH->nFGroups >= 0);
 
-  for (int type = TSDB_FILE_TYPE_HEAD; type < TSDB_FILE_TYPE_MAX; type++) {
+  for (int type = 0; type < TSDB_FILE_TYPE_MAX; type++) {
     if (remove(fileGroup.files[type].fname) < 0) {
       tsdbError("vgId:%d failed to remove file %s", REPO_ID(pRepo), fileGroup.files[type].fname);
     }
diff --git a/src/tsdb/src/tsdbMain.c b/src/tsdb/src/tsdbMain.c
index e30164592dee23c1baf86c11f44daba2f3e4ab85..772bcf48d6023f9d0070ba8c23ce8eab128ddd4e 100644
--- a/src/tsdb/src/tsdbMain.c
+++ b/src/tsdb/src/tsdbMain.c
@@ -212,59 +212,61 @@ uint32_t tsdbGetFileInfo(TSDB_REPO_T *repo, char *name, uint32_t *index, uint32_
 
   char *sdup = strdup(pRepo->rootDir);
   char *prefix = dirname(sdup);
+  int   prefixLen = strlen(prefix);
+  tfree(sdup);
 
   if (name[0] == 0) {  // get the file from index or after, but not larger than eindex
-    int fid = (*index) / 3;
+    int fid = (*index) / TSDB_FILE_TYPE_MAX;
 
     if (pFileH->nFGroups == 0 || fid > pFileH->pFGroup[pFileH->nFGroups - 1].fileId) {
       if (*index <= TSDB_META_FILE_INDEX && TSDB_META_FILE_INDEX <= eindex) {
         fname = tsdbGetMetaFileName(pRepo->rootDir);
         *index = TSDB_META_FILE_INDEX;
+        magic = TSDB_META_FILE_MAGIC(pRepo->tsdbMeta);
       } else {
-        tfree(sdup);
         return 0;
       }
     } else {
       SFileGroup *pFGroup =
           taosbsearch(&fid, pFileH->pFGroup, pFileH->nFGroups, sizeof(SFileGroup), keyFGroupCompFunc, TD_GE);
       if (pFGroup->fileId == fid) {
-        fname = strdup(pFGroup->files[(*index) % 3].fname);
+        fname = strdup(pFGroup->files[(*index) % TSDB_FILE_TYPE_MAX].fname);
+        magic = pFGroup->files[(*index) % TSDB_FILE_TYPE_MAX].info.magic;
       } else {
-        if (pFGroup->fileId * 3 + 2 < eindex) {
+        if ((pFGroup->fileId + 1) * TSDB_FILE_TYPE_MAX - 1 < eindex) {
           fname = strdup(pFGroup->files[0].fname);
-          *index = pFGroup->fileId * 3;
+          *index = pFGroup->fileId * TSDB_FILE_TYPE_MAX;
+          magic = pFGroup->files[0].info.magic;
         } else {
-          tfree(sdup);
           return 0;
         }
       }
     }
-    strcpy(name, fname + strlen(prefix));
+    strcpy(name, fname + prefixLen);
   } else {                                 // get the named file at the specified index. If not there, return 0
     if (*index == TSDB_META_FILE_INDEX) {  // get meta file
       fname = tsdbGetMetaFileName(pRepo->rootDir);
+      magic = TSDB_META_FILE_MAGIC(pRepo->tsdbMeta);
     } else {
-      int         fid = (*index) / 3;
+      int         fid = (*index) / TSDB_FILE_TYPE_MAX;
       SFileGroup *pFGroup = tsdbSearchFGroup(pFileH, fid, TD_EQ);
       if (pFGroup == NULL) {  // not found
-        tfree(sdup);
         return 0;
       }
 
-      SFile *pFile = &pFGroup->files[(*index) % 3];
+      SFile *pFile = &pFGroup->files[(*index) % TSDB_FILE_TYPE_MAX];
       fname = strdup(pFile->fname);
+      magic = pFile->info.magic;
     }
   }
 
   if (stat(fname, &fState) < 0) {
-    tfree(sdup);
     tfree(fname);
     return 0;
   }
 
-  tfree(sdup);
   *size = fState.st_size;
-  magic = *size;
+  // magic = *size;
 
   tfree(fname);
   return magic;
@@ -793,7 +795,8 @@ static int tsdbRestoreInfo(STsdbRepo *pRepo) {
     for (int i = 1; i < pRepo->config.maxTables; i++) {
       STable *pTable = pMeta->tables[i];
       if (pTable == NULL) continue;
-      SCompIdx *pIdx = &rhelper.pCompIdx[i];
+      tsdbSetHelperTable(&rhelper, pTable, pRepo);
+      SCompIdx *pIdx = &(rhelper.curCompIdx);
 
       if (pIdx->offset > 0 && pTable->lastKey < pIdx->maxKey) pTable->lastKey = pIdx->maxKey;
     }
diff --git a/src/tsdb/src/tsdbMemTable.c b/src/tsdb/src/tsdbMemTable.c
index 1b7db635b337e2576ac61ac100dabad91be793df..5325eb5b0cc24b11884191645601b9d3c4c5d2eb 100644
--- a/src/tsdb/src/tsdbMemTable.c
+++ b/src/tsdb/src/tsdbMemTable.c
@@ -627,9 +627,12 @@ static int tsdbCommitToFile(STsdbRepo *pRepo, int fid, SCommitIter *iters, SRWHe
   tsdbCloseHelperFile(pHelper, 0);
 
   pthread_rwlock_wrlock(&(pFileH->fhlock));
-  pGroup->files[TSDB_FILE_TYPE_HEAD] = pHelper->files.headF;
-  pGroup->files[TSDB_FILE_TYPE_DATA] = pHelper->files.dataF;
-  pGroup->files[TSDB_FILE_TYPE_LAST] = pHelper->files.lastF;
+#ifdef TSDB_IDX
+  pGroup->files[TSDB_FILE_TYPE_IDX] = *(helperIdxF(pHelper));
+#endif
+  pGroup->files[TSDB_FILE_TYPE_HEAD] = *(helperHeadF(pHelper));
+  pGroup->files[TSDB_FILE_TYPE_DATA] = *(helperDataF(pHelper));
+  pGroup->files[TSDB_FILE_TYPE_LAST] = *(helperLastF(pHelper));
   pthread_rwlock_unlock(&(pFileH->fhlock));
 
   return 0;
diff --git a/src/tsdb/src/tsdbRWHelper.c b/src/tsdb/src/tsdbRWHelper.c
index 0d52b7ae3348f588871424f97a5c1476b150963c..f8792469cbcd4699046856d4f41bdaf0e789a0dc 100644
--- a/src/tsdb/src/tsdbRWHelper.c
+++ b/src/tsdb/src/tsdbRWHelper.c
@@ -99,6 +99,7 @@ void tsdbResetHelper(SRWHelper *pHelper) {
 
 int tsdbSetAndOpenHelperFile(SRWHelper *pHelper, SFileGroup *pGroup) {
   ASSERT(pHelper != NULL && pGroup != NULL);
+  SFile *pFile = NULL;
 
   // Clear the helper object
   tsdbResetHelper(pHelper);
@@ -106,44 +107,51 @@ int tsdbSetAndOpenHelperFile(SRWHelper *pHelper, SFileGroup *pGroup) {
   ASSERT(pHelper->state == TSDB_HELPER_CLEAR_STATE);
 
   // Set the files
-  pHelper->files.fid = pGroup->fileId;
-  pHelper->files.headF = pGroup->files[TSDB_FILE_TYPE_HEAD];
-  pHelper->files.dataF = pGroup->files[TSDB_FILE_TYPE_DATA];
-  pHelper->files.lastF = pGroup->files[TSDB_FILE_TYPE_LAST];
+  pHelper->files.fGroup = *pGroup;
   if (helperType(pHelper) == TSDB_WRITE_HELPER) {
-    tsdbGetDataFileName(pHelper->pRepo, pGroup->fileId, TSDB_FILE_TYPE_NHEAD, pHelper->files.nHeadF.fname);
-    tsdbGetDataFileName(pHelper->pRepo, pGroup->fileId, TSDB_FILE_TYPE_NLAST, pHelper->files.nLastF.fname);
+#ifdef TSDB_IDX
+    tsdbGetDataFileName(pHelper->pRepo, pGroup->fileId, TSDB_FILE_TYPE_NIDX, helperNewIdxF(pHelper)->fname);
+#endif
+    tsdbGetDataFileName(pHelper->pRepo, pGroup->fileId, TSDB_FILE_TYPE_NHEAD, helperNewHeadF(pHelper)->fname);
+    tsdbGetDataFileName(pHelper->pRepo, pGroup->fileId, TSDB_FILE_TYPE_NLAST, helperNewLastF(pHelper)->fname);
   }
 
   // Open the files
-  if (tsdbOpenFile(&(pHelper->files.headF), O_RDONLY) < 0) goto _err;
+#ifdef TSDB_IDX
+  if (tsdbOpenFile(helperIdxF(pHelper), O_RDONLY) < 0) goto _err;
+#endif
+  if (tsdbOpenFile(helperHeadF(pHelper), O_RDONLY) < 0) goto _err;
   if (helperType(pHelper) == TSDB_WRITE_HELPER) {
-    if (tsdbOpenFile(&(pHelper->files.dataF), O_RDWR) < 0) goto _err;
-    if (tsdbOpenFile(&(pHelper->files.lastF), O_RDWR) < 0) goto _err;
+    if (tsdbOpenFile(helperDataF(pHelper), O_RDWR) < 0) goto _err;
+    if (tsdbOpenFile(helperLastF(pHelper), O_RDWR) < 0) goto _err;
+
+#ifdef TSDB_IDX
+    // Create and open .i file
+    pFile = helperNewIdxF(pHelper);
+    if (tsdbOpenFile(pFile, O_WRONLY | O_CREAT) < 0) return -1;
+    pFile->info.size = TSDB_FILE_HEAD_SIZE;
+    pFile->info.magic = TSDB_FILE_INIT_MAGIC;
+    if (tsdbUpdateFileHeader(pFile, 0) < 0) return -1;
+#endif
 
     // Create and open .h
-    if (tsdbOpenFile(&(pHelper->files.nHeadF), O_WRONLY | O_CREAT) < 0) return -1;
-    // size_t tsize = TSDB_FILE_HEAD_SIZE + sizeof(SCompIdx) * pCfg->maxTables + sizeof(TSCKSUM);
-    if (tsendfile(pHelper->files.nHeadF.fd, pHelper->files.headF.fd, NULL, TSDB_FILE_HEAD_SIZE) < TSDB_FILE_HEAD_SIZE) {
-      tsdbError("vgId:%d failed to sendfile %d bytes from file %s to %s since %s", REPO_ID(pHelper->pRepo),
-                TSDB_FILE_HEAD_SIZE, pHelper->files.headF.fname, pHelper->files.nHeadF.fname, strerror(errno));
-      terrno = TAOS_SYSTEM_ERROR(errno);
-      goto _err;
-    }
+    pFile = helperNewHeadF(pHelper);
+    if (tsdbOpenFile(pFile, O_WRONLY | O_CREAT) < 0) return -1;
+    pFile->info.size = TSDB_FILE_HEAD_SIZE;
+    pFile->info.magic = TSDB_FILE_INIT_MAGIC;
+    if (tsdbUpdateFileHeader(pFile, 0) < 0) return -1;
 
     // Create and open .l file if should
     if (tsdbShouldCreateNewLast(pHelper)) {
-      if (tsdbOpenFile(&(pHelper->files.nLastF), O_WRONLY | O_CREAT) < 0) goto _err;
-      if (tsendfile(pHelper->files.nLastF.fd, pHelper->files.lastF.fd, NULL, TSDB_FILE_HEAD_SIZE) < TSDB_FILE_HEAD_SIZE) {
-        tsdbError("vgId:%d failed to sendfile %d bytes from file %s to %s since %s", REPO_ID(pHelper->pRepo),
-                  TSDB_FILE_HEAD_SIZE, pHelper->files.lastF.fname, pHelper->files.nLastF.fname, strerror(errno));
-        terrno = TAOS_SYSTEM_ERROR(errno);
-        goto _err;
-      }
+      pFile = helperNewLastF(pHelper);
+      if (tsdbOpenFile(pFile, O_WRONLY | O_CREAT) < 0) goto _err;
+      pFile->info.size = TSDB_FILE_HEAD_SIZE;
+      pFile->info.magic = TSDB_FILE_INIT_MAGIC;
+      if (tsdbUpdateFileHeader(pFile, 0) < 0) return -1;
     }
   } else {
-    if (tsdbOpenFile(&(pHelper->files.dataF), O_RDONLY) < 0) goto _err;
-    if (tsdbOpenFile(&(pHelper->files.lastF), O_RDONLY) < 0) goto _err;
+    if (tsdbOpenFile(helperDataF(pHelper), O_RDONLY) < 0) goto _err;
+    if (tsdbOpenFile(helperLastF(pHelper), O_RDONLY) < 0) goto _err;
   }
 
   helperSetState(pHelper, TSDB_HELPER_FILE_SET_AND_OPEN);
@@ -155,59 +163,98 @@ _err:
 }
 
 int tsdbCloseHelperFile(SRWHelper *pHelper, bool hasError) {
-  if (pHelper->files.headF.fd > 0) {
-    close(pHelper->files.headF.fd);
-    pHelper->files.headF.fd = -1;
+  SFile *pFile = NULL;
+
+#ifdef TSDB_IDX
+  pFile = helperIdxF(pHelper);
+  if (pFile->fd > 0) {
+    close(pFile->fd);
+    pFile->fd = -1;
+  }
+#endif
+
+  pFile = helperHeadF(pHelper);
+  if (pFile->fd > 0) {
+    close(pFile->fd);
+    pFile->fd = -1;
   }
-  if (pHelper->files.dataF.fd > 0) {
+
+  pFile = helperDataF(pHelper);
+  if (pFile->fd > 0) {
     if (helperType(pHelper) == TSDB_WRITE_HELPER) {
-      tsdbUpdateFileHeader(&(pHelper->files.dataF), 0);
-      fsync(pHelper->files.dataF.fd);
+      tsdbUpdateFileHeader(pFile, 0);
+      fsync(pFile->fd);
     }
-    close(pHelper->files.dataF.fd);
-    pHelper->files.dataF.fd = -1;
+    close(pFile->fd);
+    pFile->fd = -1;
   }
-  if (pHelper->files.lastF.fd > 0) {
-    if (helperType(pHelper) == TSDB_WRITE_HELPER) {
-      fsync(pHelper->files.lastF.fd);
+
+  pFile = helperLastF(pHelper);
+  if (pFile->fd > 0) {
+    if (helperType(pHelper) == TSDB_WRITE_HELPER && !TSDB_NLAST_FILE_OPENED(pHelper)) {
+      fsync(pFile->fd);
     }
-    close(pHelper->files.lastF.fd);
-    pHelper->files.lastF.fd = -1;
+    close(pFile->fd);
+    pFile->fd = -1;
   }
+
   if (helperType(pHelper) == TSDB_WRITE_HELPER) {
-    if (pHelper->files.nHeadF.fd > 0) {
-      if (!hasError) tsdbUpdateFileHeader(&(pHelper->files.nHeadF), 0);
-      fsync(pHelper->files.nHeadF.fd);
-      close(pHelper->files.nHeadF.fd);
-      pHelper->files.nHeadF.fd = -1;
+#ifdef TSDB_IDX
+    pFile = helperNewIdxF(pHelper);
+    if (pFile->fd > 0) {
+      if (!hasError) tsdbUpdateFileHeader(pFile, 0);
+      fsync(pFile->fd);
+      close(pFile->fd);
+      pFile->fd = -1;
       if (hasError) {
-        (void)remove(pHelper->files.nHeadF.fname);
+        (void)remove(pFile->fname);
       } else {
-        if (rename(pHelper->files.nHeadF.fname, pHelper->files.headF.fname) < 0) {
-          tsdbError("failed to rename file from %s to %s since %s", pHelper->files.nHeadF.fname,
-                    pHelper->files.headF.fname, strerror(errno));
+        if (rename(pFile->fname, helperIdxF(pHelper)->fname) < 0) {
+          tsdbError("failed to rename file from %s to %s since %s", pFile->fname, helperIdxF(pHelper)->fname,
+                    strerror(errno));
           terrno = TAOS_SYSTEM_ERROR(errno);
           return -1;
         }
-        pHelper->files.headF.info = pHelper->files.nHeadF.info;
+        helperIdxF(pHelper)->info = pFile->info;
+      }
+    }
+#endif
+
+    pFile = helperNewHeadF(pHelper);
+    if (pFile->fd > 0) {
+      if (!hasError) tsdbUpdateFileHeader(pFile, 0);
+      fsync(pFile->fd);
+      close(pFile->fd);
+      pFile->fd = -1;
+      if (hasError) {
+        (void)remove(pFile->fname);
+      } else {
+        if (rename(pFile->fname, helperHeadF(pHelper)->fname) < 0) {
+          tsdbError("failed to rename file from %s to %s since %s", pFile->fname, helperHeadF(pHelper)->fname,
+                    strerror(errno));
+          terrno = TAOS_SYSTEM_ERROR(errno);
+          return -1;
+        }
+        helperHeadF(pHelper)->info = pFile->info;
       }
     }
 
-    if (pHelper->files.nLastF.fd > 0) {
-      if (!hasError) tsdbUpdateFileHeader(&(pHelper->files.nLastF), 0);
-      fsync(pHelper->files.nLastF.fd);
-      close(pHelper->files.nLastF.fd);
-      pHelper->files.nLastF.fd = -1;
+    pFile = helperNewLastF(pHelper);
+    if (pFile->fd > 0) {
+      if (!hasError) tsdbUpdateFileHeader(pFile, 0);
+      fsync(pFile->fd);
+      close(pFile->fd);
+      pFile->fd = -1;
       if (hasError) {
-        (void)remove(pHelper->files.nLastF.fname);
+        (void)remove(pFile->fname);
       } else {
-        if (rename(pHelper->files.nLastF.fname, pHelper->files.lastF.fname) < 0) {
-          tsdbError("failed to rename file from %s to %s since %s", pHelper->files.nLastF.fname,
-                    pHelper->files.lastF.fname, strerror(errno));
+        if (rename(pFile->fname, helperLastF(pHelper)->fname) < 0) {
+          tsdbError("failed to rename file from %s to %s since %s", pFile->fname, helperLastF(pHelper)->fname,
+                    strerror(errno));
           terrno = TAOS_SYSTEM_ERROR(errno);
           return -1;
         }
-        pHelper->files.lastF.info = pHelper->files.nLastF.info;
+        helperLastF(pHelper)->info = helperNewLastF(pHelper)->info;
       }
     }
   }
@@ -224,18 +271,35 @@ void tsdbSetHelperTable(SRWHelper *pHelper, STable *pTable, STsdbRepo *pRepo) {
   pHelper->tableInfo.tid = pTable->tableId.tid;
   pHelper->tableInfo.uid = pTable->tableId.uid;
   STSchema *pSchema = tsdbGetTableSchemaImpl(pTable, false, false, -1);
-  pHelper->tableInfo.sversion = schemaVersion(pSchema);
 
   tdInitDataCols(pHelper->pDataCols[0], pSchema);
   tdInitDataCols(pHelper->pDataCols[1], pSchema);
 
-  SCompIdx *pIdx = pHelper->pCompIdx + pTable->tableId.tid;
-  if (pIdx->offset > 0) {
-    if (pIdx->uid != TABLE_UID(pTable)) {
-      memset((void *)pIdx, 0, sizeof(SCompIdx));
-    } else {
-      if (pIdx->hasLast) pHelper->hasOldLastBlock = true;
+  if (pHelper->idxH.numOfIdx > 0) {
+    while (true) {
+      if (pHelper->idxH.curIdx >= pHelper->idxH.numOfIdx) {
+        memset(&(pHelper->curCompIdx), 0, sizeof(SCompIdx));
+        break;
+      }
+
+      SCompIdx *pIdx = &(pHelper->idxH.pIdxArray[pHelper->idxH.curIdx]);
+      if (pIdx->tid == TABLE_TID(pTable)) {
+        if (pIdx->uid == TABLE_UID(pTable)) {
+          pHelper->curCompIdx = *pIdx;
+        } else {
+          memset(&(pHelper->curCompIdx), 0, sizeof(SCompIdx));
+        }
+        pHelper->idxH.curIdx++;
+        break;
+      } else if (pIdx->tid > TABLE_TID(pTable)) {
+        memset(&(pHelper->curCompIdx), 0, sizeof(SCompIdx));
+        break;
+      } else {
+        pHelper->idxH.curIdx++;
+      }
     }
+  } else {
+    memset(&(pHelper->curCompIdx), 0, sizeof(SCompIdx));
   }
 
   helperSetState(pHelper, TSDB_HELPER_TABLE_SET);
@@ -245,8 +309,8 @@ void tsdbSetHelperTable(SRWHelper *pHelper, STable *pTable, STsdbRepo *pRepo) {
 int tsdbCommitTableData(SRWHelper *pHelper, SCommitIter *pCommitIter, SDataCols *pDataCols, TSKEY maxKey) {
   ASSERT(helperType(pHelper) == TSDB_WRITE_HELPER);
 
-  SCompIdx * pIdx = &(pHelper->pCompIdx[TABLE_TID(pCommitIter->pTable)]);
-  int        blkIdx = 0;
+  SCompIdx *pIdx = &(pHelper->curCompIdx);
+  int       blkIdx = 0;
 
   ASSERT(pIdx->offset == 0 || pIdx->uid == TABLE_UID(pCommitIter->pTable));
   if (tsdbLoadCompInfo(pHelper, NULL) < 0) return -1;
@@ -271,44 +335,53 @@ int tsdbMoveLastBlockIfNeccessary(SRWHelper *pHelper) {
   STsdbCfg *pCfg = &pHelper->pRepo->config;
 
   ASSERT(helperType(pHelper) == TSDB_WRITE_HELPER);
-  SCompIdx * pIdx = pHelper->pCompIdx + pHelper->tableInfo.tid;
+  SCompIdx * pIdx = &(pHelper->curCompIdx);
   SCompBlock compBlock = {0};
   if (TSDB_NLAST_FILE_OPENED(pHelper) && (pHelper->hasOldLastBlock)) {
     if (tsdbLoadCompInfo(pHelper, NULL) < 0) return -1;
 
     SCompBlock *pCompBlock = blockAtIdx(pHelper, pIdx->numOfBlocks - 1);
     ASSERT(pCompBlock->last);
+    if (tsdbLoadBlockData(pHelper, pCompBlock, NULL) < 0) return -1;
+    ASSERT(pHelper->pDataCols[0]->numOfRows == pCompBlock->numOfRows &&
+           pHelper->pDataCols[0]->numOfRows < pCfg->minRowsPerFileBlock);
+    if (tsdbWriteBlockToFile(pHelper, helperNewLastF(pHelper), pHelper->pDataCols[0], &compBlock, true, true) < 0)
+      return -1;
 
+    if (tsdbUpdateSuperBlock(pHelper, &compBlock, pIdx->numOfBlocks - 1) < 0) return -1;
+
+#if 0
     if (pCompBlock->numOfSubBlocks > 1) {
       if (tsdbLoadBlockData(pHelper, pCompBlock, NULL) < 0) return -1;
       ASSERT(pHelper->pDataCols[0]->numOfRows == pCompBlock->numOfRows &&
              pHelper->pDataCols[0]->numOfRows < pCfg->minRowsPerFileBlock);
-      if (tsdbWriteBlockToFile(pHelper, &(pHelper->files.nLastF), pHelper->pDataCols[0], &compBlock, true, true) < 0)
+      if (tsdbWriteBlockToFile(pHelper, helperNewLastF(pHelper), pHelper->pDataCols[0], &compBlock, true, true) < 0)
         return -1;
 
       if (tsdbUpdateSuperBlock(pHelper, &compBlock, pIdx->numOfBlocks - 1) < 0) return -1;
     } else {
-      if (lseek(pHelper->files.lastF.fd, pCompBlock->offset, SEEK_SET) < 0) {
-        tsdbError("vgId:%d failed to lseek file %s since %s", REPO_ID(pHelper->pRepo), pHelper->files.lastF.fname,
+      if (lseek(helperLastF(pHelper)->fd, pCompBlock->offset, SEEK_SET) < 0) {
+        tsdbError("vgId:%d failed to lseek file %s since %s", REPO_ID(pHelper->pRepo), helperLastF(pHelper)->fname,
                   strerror(errno));
         terrno = TAOS_SYSTEM_ERROR(errno);
         return -1;
       }
-      pCompBlock->offset = lseek(pHelper->files.nLastF.fd, 0, SEEK_END);
+      pCompBlock->offset = lseek(helperNewLastF(pHelper)->fd, 0, SEEK_END);
       if (pCompBlock->offset < 0) {
-        tsdbError("vgId:%d failed to lseek file %s since %s", REPO_ID(pHelper->pRepo), pHelper->files.nLastF.fname,
+        tsdbError("vgId:%d failed to lseek file %s since %s", REPO_ID(pHelper->pRepo), helperNewLastF(pHelper)->fname,
                   strerror(errno));
         terrno = TAOS_SYSTEM_ERROR(errno);
         return -1;
       }
 
-      if (tsendfile(pHelper->files.nLastF.fd, pHelper->files.lastF.fd, NULL, pCompBlock->len) < pCompBlock->len) {
+      if (tsendfile(helperNewLastF(pHelper)->fd, helperLastF(pHelper)->fd, NULL, pCompBlock->len) < pCompBlock->len) {
         tsdbError("vgId:%d failed to sendfile from file %s to file %s since %s", REPO_ID(pHelper->pRepo),
-                  pHelper->files.lastF.fname, pHelper->files.nLastF.fname, strerror(errno));
+                  helperLastF(pHelper)->fname, helperNewLastF(pHelper)->fname, strerror(errno));
         terrno = TAOS_SYSTEM_ERROR(errno);
         return -1;
       }
     }
+#endif
 
     pHelper->hasOldLastBlock = false;
   }
@@ -317,164 +390,178 @@ int tsdbMoveLastBlockIfNeccessary(SRWHelper *pHelper) {
 }
 
 int tsdbWriteCompInfo(SRWHelper *pHelper) {
-  off_t offset = 0;
-  SCompIdx *pIdx = pHelper->pCompIdx + pHelper->tableInfo.tid;
-  if (!helperHasState(pHelper, TSDB_HELPER_INFO_LOAD)) {
-    if (pIdx->offset > 0) {
-      offset = lseek(pHelper->files.nHeadF.fd, 0, SEEK_END);
-      if (offset < 0) {
-        tsdbError("vgId:%d failed to lseed file %s since %s", REPO_ID(pHelper->pRepo), pHelper->files.nHeadF.fname,
-                  strerror(errno));
-        terrno = TAOS_SYSTEM_ERROR(errno);
-        return -1;
-      }
-
-      pIdx->offset = offset;
-      ASSERT(pIdx->offset >= TSDB_FILE_HEAD_SIZE);
+  SCompIdx *pIdx = &(pHelper->curCompIdx);
+  off_t     offset = 0;
+  SFile *   pFile = helperNewHeadF(pHelper);
 
-      if (tsendfile(pHelper->files.nHeadF.fd, pHelper->files.headF.fd, NULL, pIdx->len) < pIdx->len) {
-        tsdbError("vgId:%d failed to send %d bytes from file %s to %s since %s", REPO_ID(pHelper->pRepo), pIdx->len,
-                  pHelper->files.headF.fname, pHelper->files.nHeadF.fname, strerror(errno));
-        terrno = TAOS_SYSTEM_ERROR(errno);
-        return -1;
-      }
-    }
-  } else {
-    if (pIdx->len > 0) {
+  if (pIdx->len > 0) {
+    if (!helperHasState(pHelper, TSDB_HELPER_INFO_LOAD)) {
+      if (tsdbLoadCompInfo(pHelper, NULL) < 0) return -1;
+    } else {
       pHelper->pCompInfo->delimiter = TSDB_FILE_DELIMITER;
       pHelper->pCompInfo->uid = pHelper->tableInfo.uid;
-      pHelper->pCompInfo->checksum = 0;
+      pHelper->pCompInfo->tid = pHelper->tableInfo.tid;
       ASSERT(pIdx->len > sizeof(SCompInfo) + sizeof(TSCKSUM) &&
              (pIdx->len - sizeof(SCompInfo) - sizeof(TSCKSUM)) % sizeof(SCompBlock) == 0);
       taosCalcChecksumAppend(0, (uint8_t *)pHelper->pCompInfo, pIdx->len);
-      offset = lseek(pHelper->files.nHeadF.fd, 0, SEEK_END);
-      if (offset < 0) {
-        tsdbError("vgId:%d failed to lseek file %s since %s", REPO_ID(pHelper->pRepo), pHelper->files.nHeadF.fname,
-                  strerror(errno));
-        terrno = TAOS_SYSTEM_ERROR(errno);
-        return -1;
-      }
-      pIdx->offset = offset;
-      pIdx->uid = pHelper->tableInfo.uid;
-      ASSERT(pIdx->offset >= TSDB_FILE_HEAD_SIZE);
+    }
 
-      if (twrite(pHelper->files.nHeadF.fd, (void *)(pHelper->pCompInfo), pIdx->len) < pIdx->len) {
-        tsdbError("vgId:%d failed to write %d bytes to file %s since %s", REPO_ID(pHelper->pRepo), pIdx->len,
-                  pHelper->files.nHeadF.fname, strerror(errno));
-        terrno = TAOS_SYSTEM_ERROR(errno);
+    pFile->info.magic = taosCalcChecksum(
+        pFile->info.magic, (uint8_t *)POINTER_SHIFT(pHelper->pCompInfo, pIdx->len - sizeof(TSCKSUM)), sizeof(TSCKSUM));
+    offset = lseek(pFile->fd, 0, SEEK_END);
+    if (offset < 0) {
+      tsdbError("vgId:%d failed to lseek file %s since %s", REPO_ID(pHelper->pRepo), pFile->fname, strerror(errno));
+      terrno = TAOS_SYSTEM_ERROR(errno);
+      return -1;
+    }
+    pIdx->offset = offset;
+    pIdx->uid = pHelper->tableInfo.uid;
+    pIdx->tid = pHelper->tableInfo.tid;
+    ASSERT(pIdx->offset >= TSDB_FILE_HEAD_SIZE);
+
+    if (twrite(pFile->fd, (void *)(pHelper->pCompInfo), pIdx->len) < pIdx->len) {
+      tsdbError("vgId:%d failed to write %d bytes to file %s since %s", REPO_ID(pHelper->pRepo), pIdx->len,
+                pFile->fname, strerror(errno));
+      terrno = TAOS_SYSTEM_ERROR(errno);
+      return -1;
+    }
+
+#ifdef TSDB_IDX
+    pFile = helperNewIdxF(pHelper);
+#endif
+
+    if (tsizeof(pHelper->pWIdx) < pFile->info.len + sizeof(SCompIdx) + 12) {
+      pHelper->pWIdx = trealloc(pHelper->pWIdx, tsizeof(pHelper->pWIdx) == 0 ? 1024 : tsizeof(pHelper->pWIdx) * 2);
+      if (pHelper->pWIdx == NULL) {
+        terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
         return -1;
       }
     }
+
+    void *pBuf = POINTER_SHIFT(pHelper->pWIdx, pFile->info.len);
+    pFile->info.len += tsdbEncodeSCompIdx(&pBuf, &(pHelper->curCompIdx));
   }
 
   return 0;
 }
 
 int tsdbWriteCompIdx(SRWHelper *pHelper) {
-  STsdbCfg *pCfg = &pHelper->pRepo->config;
-
   ASSERT(helperType(pHelper) == TSDB_WRITE_HELPER);
-  off_t offset = lseek(pHelper->files.nHeadF.fd, 0, SEEK_END);
+  off_t offset = 0;
+
+#ifdef TSDB_IDX
+  SFile *pFile = helperNewIdxF(pHelper);
+#else
+  SFile *pFile = helperNewHeadF(pHelper);
+#endif
+
+  pFile->info.len += sizeof(TSCKSUM);
+  if (tsizeof(pHelper->pWIdx) < pFile->info.len) {
+    pHelper->pWIdx = trealloc(pHelper->pWIdx, pFile->info.len);
+    if (pHelper->pWIdx == NULL) {
+      terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
+      return -1;
+    }
+  }
+  taosCalcChecksumAppend(0, (uint8_t *)pHelper->pWIdx, pFile->info.len);
+  pFile->info.magic = taosCalcChecksum(
+      pFile->info.magic, (uint8_t *)POINTER_SHIFT(pHelper->pWIdx, pFile->info.len - sizeof(TSCKSUM)), sizeof(TSCKSUM));
+
+  offset = lseek(pFile->fd, 0, SEEK_END);
   if (offset < 0) {
-    tsdbError("vgId:%d failed to lseek file %s to end since %s", REPO_ID(pHelper->pRepo), pHelper->files.nHeadF.fname,
-              strerror(errno));
+    tsdbError("vgId:%d failed to lseek file %s since %s", REPO_ID(pHelper->pRepo), pFile->fname, strerror(errno));
     terrno = TAOS_SYSTEM_ERROR(errno);
     return -1;
   }
 
-  SFile *pFile = &(pHelper->files.nHeadF);
   pFile->info.offset = offset;
 
-  void *buf = pHelper->pBuffer;
-  for (uint32_t i = 0; i < pCfg->maxTables; i++) {
-    SCompIdx *pCompIdx = pHelper->pCompIdx + i;
-    if (pCompIdx->offset > 0) {
-      int drift = POINTER_DISTANCE(buf, pHelper->pBuffer);
-      if (tsizeof(pHelper->pBuffer) - drift < 128) {
-        pHelper->pBuffer = trealloc(pHelper->pBuffer, tsizeof(pHelper->pBuffer) * 2);
-        if (pHelper->pBuffer == NULL) {
-          terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
-          return -1;
-        }
-      }
-      buf = POINTER_SHIFT(pHelper->pBuffer, drift);
-      taosEncodeVariantU32(&buf, i);
-      tsdbEncodeSCompIdx(&buf, pCompIdx);
-    }
-  }
-
-  int tsize = (char *)buf - (char *)pHelper->pBuffer + sizeof(TSCKSUM);
-  taosCalcChecksumAppend(0, (uint8_t *)pHelper->pBuffer, tsize);
-
-  if (twrite(pHelper->files.nHeadF.fd, (void *)pHelper->pBuffer, tsize) < tsize) {
-    tsdbError("vgId:%d failed to write %d bytes to file %s since %s", REPO_ID(pHelper->pRepo), tsize,
-              pHelper->files.nHeadF.fname, strerror(errno));
+  if (twrite(pFile->fd, (void *)pHelper->pWIdx, pFile->info.len) < pFile->info.len) {
+    tsdbError("vgId:%d failed to write %d bytes to file %s since %s", REPO_ID(pHelper->pRepo), pFile->info.len,
+              pFile->fname, strerror(errno));
     terrno = TAOS_SYSTEM_ERROR(errno);
     return -1;
   }
-  pFile->info.len = tsize;
+
   return 0;
 }
 
 int tsdbLoadCompIdx(SRWHelper *pHelper, void *target) {
-  STsdbCfg *pCfg = &(pHelper->pRepo->config);
-
   ASSERT(pHelper->state == TSDB_HELPER_FILE_SET_AND_OPEN);
+#ifdef TSDB_IDX
+  SFile *pFile = helperIdxF(pHelper);
+#else
+  SFile *pFile = helperHeadF(pHelper);
+#endif
+  int fd = pFile->fd;
 
   if (!helperHasState(pHelper, TSDB_HELPER_IDX_LOAD)) {
     // If not load from file, just load it in object
-    SFile *pFile = &(pHelper->files.headF);
-    int    fd = pFile->fd;
-
-    memset(pHelper->pCompIdx, 0, tsizeof(pHelper->pCompIdx));
-    if (pFile->info.offset > 0) {
-      ASSERT(pFile->info.offset > TSDB_FILE_HEAD_SIZE);
+    if (pFile->info.len > 0) {
+      if ((pHelper->pBuffer = trealloc(pHelper->pBuffer, pFile->info.len)) == NULL) {
+        terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
+        return -1;
+      }
 
       if (lseek(fd, pFile->info.offset, SEEK_SET) < 0) {
-        tsdbError("vgId:%d failed to lseek file %s to %u since %s", REPO_ID(pHelper->pRepo), pFile->fname,
-                  pFile->info.offset, strerror(errno));
+        tsdbError("vgId:%d failed to lseek file %s since %s", REPO_ID(pHelper->pRepo), pFile->fname, strerror(errno));
         terrno = TAOS_SYSTEM_ERROR(errno);
         return -1;
       }
-      if ((pHelper->pBuffer = trealloc(pHelper->pBuffer, pFile->info.len)) == NULL) {
-        terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
-        return -1;
-      }
+
       if (tread(fd, (void *)(pHelper->pBuffer), pFile->info.len) < pFile->info.len) {
         tsdbError("vgId:%d failed to read %d bytes from file %s since %s", REPO_ID(pHelper->pRepo), pFile->info.len,
                   pFile->fname, strerror(errno));
         terrno = TAOS_SYSTEM_ERROR(errno);
         return -1;
       }
+
       if (!taosCheckChecksumWhole((uint8_t *)(pHelper->pBuffer), pFile->info.len)) {
-        tsdbError("vgId:%d file %s SCompIdx part is corrupted. offset %u len %u", REPO_ID(pHelper->pRepo), pFile->fname,
-                  pFile->info.offset, pFile->info.len);
+        tsdbError("vgId:%d file %s SCompIdx part is corrupted. len %u", REPO_ID(pHelper->pRepo), pFile->fname,
+                  pFile->info.len);
         terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
         return -1;
       }
 
       // Decode it
+      pHelper->idxH.numOfIdx = 0;
       void *ptr = pHelper->pBuffer;
       while (POINTER_DISTANCE(ptr, pHelper->pBuffer) < (pFile->info.len - sizeof(TSCKSUM))) {
-        uint32_t tid = 0;
-        if ((ptr = taosDecodeVariantU32(ptr, &tid)) == NULL) return -1;
-        ASSERT(tid > 0 && tid < pCfg->maxTables);
+        size_t tlen = tsizeof(pHelper->idxH.pIdxArray);
+        pHelper->idxH.numOfIdx++;
 
-        if ((ptr = tsdbDecodeSCompIdx(ptr, pHelper->pCompIdx + tid)) == NULL) return -1;
+        if (tlen < pHelper->idxH.numOfIdx * sizeof(SCompIdx)) {
+          pHelper->idxH.pIdxArray = (SCompIdx *)trealloc(pHelper->idxH.pIdxArray, (tlen == 0) ? 1024 : tlen * 2);
+          if (pHelper->idxH.pIdxArray == NULL) {
+            terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
+            return -1;
+          }
+        }
 
-        ASSERT(POINTER_DISTANCE(ptr, pHelper->pBuffer) <= pFile->info.len - sizeof(TSCKSUM));
-      }
+        ptr = tsdbDecodeSCompIdx(ptr, &(pHelper->idxH.pIdxArray[pHelper->idxH.numOfIdx - 1]));
+        if (ptr == NULL) {
+          tsdbError("vgId:%d file %s SCompIdx part is corrupted. len %u", REPO_ID(pHelper->pRepo), pFile->fname,
+                    pFile->info.len);
+          terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
+          return -1;
+        }
 
-      if (lseek(fd, TSDB_FILE_HEAD_SIZE, SEEK_SET) < 0) {
-        terrno = TAOS_SYSTEM_ERROR(errno);
-        return -1;
+        ASSERT(pHelper->idxH.numOfIdx == 1 || pHelper->idxH.pIdxArray[pHelper->idxH.numOfIdx - 1].tid >
+                                                  pHelper->idxH.pIdxArray[pHelper->idxH.numOfIdx - 2].tid);
+
+        ASSERT(POINTER_DISTANCE(ptr, pHelper->pBuffer) <= pFile->info.len - sizeof(TSCKSUM));
       }
     }
   }
   helperSetState(pHelper, TSDB_HELPER_IDX_LOAD);
 
+  if (helperType(pHelper) == TSDB_WRITE_HELPER) {
+    pFile->info.len = 0;
+  }
+
   // Copy the memory for outside usage
-  if (target) memcpy(target, pHelper->pCompIdx, tsizeof(pHelper->pCompIdx));
+  if (target && pHelper->idxH.numOfIdx > 0)
+    memcpy(target, pHelper->idxH.pIdxArray, sizeof(SCompIdx) * pHelper->idxH.numOfIdx);
 
   return 0;
 }
@@ -482,15 +569,15 @@ int tsdbLoadCompIdx(SRWHelper *pHelper, void *target) {
 int tsdbLoadCompInfo(SRWHelper *pHelper, void *target) {
   ASSERT(helperHasState(pHelper, TSDB_HELPER_TABLE_SET));
 
-  SCompIdx *pIdx = pHelper->pCompIdx + pHelper->tableInfo.tid;
+  SCompIdx *pIdx = &(pHelper->curCompIdx);
 
-  int fd = pHelper->files.headF.fd;
+  int fd = helperHeadF(pHelper)->fd;
 
   if (!helperHasState(pHelper, TSDB_HELPER_INFO_LOAD)) {
     if (pIdx->offset > 0) {
       ASSERT(pIdx->uid == pHelper->tableInfo.uid);
       if (lseek(fd, pIdx->offset, SEEK_SET) < 0) {
-        tsdbError("vgId:%d failed to lseek file %s since %s", REPO_ID(pHelper->pRepo), pHelper->files.headF.fname,
+        tsdbError("vgId:%d failed to lseek file %s since %s", REPO_ID(pHelper->pRepo), helperHeadF(pHelper)->fname,
                   strerror(errno));
         terrno = TAOS_SYSTEM_ERROR(errno);
         return -1;
@@ -499,18 +586,18 @@ int tsdbLoadCompInfo(SRWHelper *pHelper, void *target) {
       pHelper->pCompInfo = trealloc((void *)pHelper->pCompInfo, pIdx->len);
       if (tread(fd, (void *)(pHelper->pCompInfo), pIdx->len) < pIdx->len) {
         tsdbError("vgId:%d failed to read %d bytes from file %s since %s", REPO_ID(pHelper->pRepo), pIdx->len,
-                  pHelper->files.headF.fname, strerror(errno));
+                  helperHeadF(pHelper)->fname, strerror(errno));
         terrno = TAOS_SYSTEM_ERROR(errno);
         return -1;
       }
       if (!taosCheckChecksumWhole((uint8_t *)pHelper->pCompInfo, pIdx->len)) {
         tsdbError("vgId:%d file %s SCompInfo part is corrupted, tid %d uid %" PRIu64, REPO_ID(pHelper->pRepo),
-                  pHelper->files.headF.fname, pHelper->tableInfo.tid, pHelper->tableInfo.uid);
+                  helperHeadF(pHelper)->fname, pHelper->tableInfo.tid, pHelper->tableInfo.uid);
         terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
         return -1;
       }
 
-      ASSERT(pIdx->uid == pHelper->pCompInfo->uid);
+      ASSERT(pIdx->uid == pHelper->pCompInfo->uid && pIdx->tid == pHelper->pCompInfo->tid);
     }
 
     helperSetState(pHelper, TSDB_HELPER_INFO_LOAD);
@@ -523,7 +610,7 @@ int tsdbLoadCompInfo(SRWHelper *pHelper, void *target) {
 
 int tsdbLoadCompData(SRWHelper *pHelper, SCompBlock *pCompBlock, void *target) {
   ASSERT(pCompBlock->numOfSubBlocks <= 1);
-  SFile *pFile = (pCompBlock->last) ? &(pHelper->files.lastF) : &(pHelper->files.dataF);
+  SFile *pFile = (pCompBlock->last) ? helperLastF(pHelper) : helperDataF(pHelper);
 
   if (lseek(pFile->fd, pCompBlock->offset, SEEK_SET) < 0) {
     tsdbError("vgId:%d failed to lseek file %s since %s", REPO_ID(pHelper->pRepo), pFile->fname, strerror(errno));
@@ -642,9 +729,9 @@ _err:
 
 // ---------------------- INTERNAL FUNCTIONS ----------------------
 static bool tsdbShouldCreateNewLast(SRWHelper *pHelper) {
-  ASSERT(pHelper->files.lastF.fd > 0);
+  ASSERT(helperLastF(pHelper)->fd > 0);
   struct stat st;
-  if (fstat(pHelper->files.lastF.fd, &st) < 0) return true;
+  if (fstat(helperLastF(pHelper)->fd, &st) < 0) return true;
   if (st.st_size > 32 * 1024 + TSDB_FILE_HEAD_SIZE) return true;
   return false;
 }
@@ -729,6 +816,8 @@ static int tsdbWriteBlockToFile(SRWHelper *pHelper, SFile *pFile, SDataCols *pDa
     ASSERT(flen > 0);
     flen += sizeof(TSCKSUM);
     taosCalcChecksumAppend(0, (uint8_t *)tptr, flen);
+    pFile->info.magic =
+        taosCalcChecksum(pFile->info.magic, (uint8_t *)POINTER_SHIFT(tptr, flen - sizeof(TSCKSUM)), sizeof(TSCKSUM));
 
     if (ncol != 0) {
       pCompCol->offset = toffset;
@@ -747,6 +836,8 @@ static int tsdbWriteBlockToFile(SRWHelper *pHelper, SFile *pFile, SDataCols *pDa
   pCompData->numOfCols = nColsNotAllNull;
 
   taosCalcChecksumAppend(0, (uint8_t *)pCompData, tsize);
+  pFile->info.magic = taosCalcChecksum(pFile->info.magic, (uint8_t *)POINTER_SHIFT(pCompData, tsize - sizeof(TSCKSUM)),
+                                       sizeof(TSCKSUM));
 
   // Write the whole block to file
   if (twrite(pFile->fd, (void *)pCompData, lsize) < lsize) {
@@ -804,7 +895,7 @@ static int tsdbAdjustInfoSizeIfNeeded(SRWHelper *pHelper, size_t esize) {
 }
 
 static int tsdbInsertSuperBlock(SRWHelper *pHelper, SCompBlock *pCompBlock, int blkIdx) {
-  SCompIdx *pIdx = pHelper->pCompIdx + pHelper->tableInfo.tid;
+  SCompIdx *pIdx = &(pHelper->curCompIdx);
 
   ASSERT(blkIdx >= 0 && blkIdx <= pIdx->numOfBlocks);
   ASSERT(pCompBlock->numOfSubBlocks == 1);
@@ -851,7 +942,7 @@ _err:
 static int tsdbAddSubBlock(SRWHelper *pHelper, SCompBlock *pCompBlock, int blkIdx, int rowsAdded) {
   ASSERT(pCompBlock->numOfSubBlocks == 0);
 
-  SCompIdx *pIdx = pHelper->pCompIdx + pHelper->tableInfo.tid;
+  SCompIdx *pIdx = &(pHelper->curCompIdx);
   ASSERT(blkIdx >= 0 && blkIdx < pIdx->numOfBlocks);
 
   SCompBlock *pSCompBlock = pHelper->pCompInfo->blocks + blkIdx;
@@ -935,7 +1026,7 @@ _err:
 static int tsdbUpdateSuperBlock(SRWHelper *pHelper, SCompBlock *pCompBlock, int blkIdx) {
   ASSERT(pCompBlock->numOfSubBlocks == 1);
 
-  SCompIdx *pIdx = pHelper->pCompIdx + pHelper->tableInfo.tid;
+  SCompIdx *pIdx = &(pHelper->curCompIdx);
 
   ASSERT(blkIdx >= 0 && blkIdx < pIdx->numOfBlocks);
 
@@ -971,24 +1062,21 @@ static int tsdbUpdateSuperBlock(SRWHelper *pHelper, SCompBlock *pCompBlock, int
 }
 
 static void tsdbResetHelperFileImpl(SRWHelper *pHelper) {
+  pHelper->idxH.numOfIdx = 0;
+  pHelper->idxH.curIdx = 0;
   memset((void *)&pHelper->files, 0, sizeof(pHelper->files));
-  pHelper->files.fid = -1;
-  pHelper->files.headF.fd = -1;
-  pHelper->files.dataF.fd = -1;
-  pHelper->files.lastF.fd = -1;
-  pHelper->files.nHeadF.fd = -1;
-  pHelper->files.nLastF.fd = -1;
+  helperHeadF(pHelper)->fd = -1;
+  helperDataF(pHelper)->fd = -1;
+  helperLastF(pHelper)->fd = -1;
+  helperNewHeadF(pHelper)->fd = -1;
+  helperNewLastF(pHelper)->fd = -1;
+#ifdef TSDB_IDX
+  helperIdxF(pHelper)->fd = -1;
+  helperNewIdxF(pHelper)->fd = -1;
+#endif
 }
 
 static int tsdbInitHelperFile(SRWHelper *pHelper) {
-  STsdbCfg *pCfg = &pHelper->pRepo->config;
-  size_t    tsize = sizeof(SCompIdx) * pCfg->maxTables + sizeof(TSCKSUM);
-  pHelper->pCompIdx = (SCompIdx *)tmalloc(tsize);
-  if (pHelper->pCompIdx == NULL) {
-    terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
-    return -1;
-  }
-
   tsdbResetHelperFileImpl(pHelper);
   return 0;
 }
@@ -996,7 +1084,8 @@ static int tsdbInitHelperFile(SRWHelper *pHelper) {
 static void tsdbDestroyHelperFile(SRWHelper *pHelper) {
   tsdbCloseHelperFile(pHelper, false);
   tsdbResetHelperFileImpl(pHelper);
-  tzfree(pHelper->pCompIdx);
+  tzfree(pHelper->idxH.pIdxArray);
+  tzfree(pHelper->pWIdx);
 }
 
 // ---------- Operations on Helper Table part
@@ -1154,7 +1243,7 @@ static int tsdbLoadBlockDataColsImpl(SRWHelper *pHelper, SCompBlock *pCompBlock,
   ASSERT(pCompBlock->numOfSubBlocks <= 1);
   ASSERT(colIds[0] == 0);
 
-  SFile *  pFile = (pCompBlock->last) ? &(pHelper->files.lastF) : &(pHelper->files.dataF);
+  SFile *  pFile = (pCompBlock->last) ? helperLastF(pHelper) : helperDataF(pHelper);
   SCompCol compCol = {0};
 
   // If only load timestamp column, no need to load SCompData part
@@ -1215,7 +1304,7 @@ _err:
 static int tsdbLoadBlockDataImpl(SRWHelper *pHelper, SCompBlock *pCompBlock, SDataCols *pDataCols) {
   ASSERT(pCompBlock->numOfSubBlocks <= 1);
 
-  SFile *pFile = (pCompBlock->last) ? &(pHelper->files.lastF) : &(pHelper->files.dataF);
+  SFile *pFile = (pCompBlock->last) ? helperLastF(pHelper) : helperDataF(pHelper);
 
   pHelper->pBuffer = trealloc(pHelper->pBuffer, pCompBlock->len);
   if (pHelper->pBuffer == NULL) {
@@ -1314,6 +1403,7 @@ _err:
 static int tsdbEncodeSCompIdx(void **buf, SCompIdx *pIdx) {
   int tlen = 0;
 
+  tlen += taosEncodeVariantI32(buf, pIdx->tid);
   tlen += taosEncodeVariantU32(buf, pIdx->len);
   tlen += taosEncodeVariantU32(buf, pIdx->offset);
   tlen += taosEncodeFixedU8(buf, pIdx->hasLast);
@@ -1329,6 +1419,7 @@ static void *tsdbDecodeSCompIdx(void *buf, SCompIdx *pIdx) {
   uint32_t numOfBlocks = 0;
   uint64_t value = 0;
 
+  if ((buf = taosDecodeVariantI32(buf, &(pIdx->tid))) == NULL) return NULL;
   if ((buf = taosDecodeVariantU32(buf, &(pIdx->len))) == NULL) return NULL;
   if ((buf = taosDecodeVariantU32(buf, &(pIdx->offset))) == NULL) return NULL;
   if ((buf = taosDecodeFixedU8(buf, &(hasLast))) == NULL) return NULL;
@@ -1346,7 +1437,7 @@ static void *tsdbDecodeSCompIdx(void *buf, SCompIdx *pIdx) {
 static int tsdbProcessAppendCommit(SRWHelper *pHelper, SCommitIter *pCommitIter, SDataCols *pDataCols, TSKEY maxKey) {
   STsdbCfg * pCfg = &(pHelper->pRepo->config);
   STable *   pTable = pCommitIter->pTable;
-  SCompIdx * pIdx = pHelper->pCompIdx + TABLE_TID(pTable);
+  SCompIdx * pIdx = &(pHelper->curCompIdx);
   TSKEY      keyFirst = tsdbNextIterKey(pCommitIter->pIter);
   int        defaultRowsInBlock = pCfg->maxRowsPerFileBlock * 4 / 5;
   SCompBlock compBlock = {0};
@@ -1362,7 +1453,7 @@ static int tsdbProcessAppendCommit(SRWHelper *pHelper, SCommitIter *pCommitIter,
     ASSERT(rowsRead > 0 && rowsRead == pDataCols->numOfRows);
     if (rowsRead + pCompBlock->numOfRows < pCfg->minRowsPerFileBlock &&
         pCompBlock->numOfSubBlocks < TSDB_MAX_SUBBLOCKS && !TSDB_NLAST_FILE_OPENED(pHelper)) {
-      if (tsdbWriteBlockToFile(pHelper, &(pHelper->files.lastF), pDataCols, &compBlock, true, false) < 0) return -1;
+      if (tsdbWriteBlockToFile(pHelper, helperLastF(pHelper), pDataCols, &compBlock, true, false) < 0) return -1;
       if (tsdbAddSubBlock(pHelper, &compBlock, pIdx->numOfBlocks - 1, rowsRead) < 0) return -1;
     } else {
       if (tsdbLoadBlockData(pHelper, pCompBlock, NULL) < 0) return -1;
@@ -1393,7 +1484,7 @@ static int tsdbProcessMergeCommit(SRWHelper *pHelper, SCommitIter *pCommitIter,
                                   int *blkIdx) {
   STsdbCfg * pCfg = &(pHelper->pRepo->config);
   STable *   pTable = pCommitIter->pTable;
-  SCompIdx * pIdx = pHelper->pCompIdx + TABLE_TID(pTable);
+  SCompIdx * pIdx = &(pHelper->curCompIdx);
   SCompBlock compBlock = {0};
   TSKEY      keyFirst = tsdbNextIterKey(pCommitIter->pIter);
   int        defaultRowsInBlock = pCfg->maxRowsPerFileBlock * 4 / 5;
@@ -1427,7 +1518,7 @@ static int tsdbProcessMergeCommit(SRWHelper *pHelper, SCommitIter *pCommitIter,
         int rowsRead = tsdbLoadDataFromCache(pTable, pCommitIter->pIter, maxKey, rows1, pDataCols,
                                              pDataCols0->cols[0].pData, pDataCols0->numOfRows);
         ASSERT(rowsRead == rows2 && rowsRead == pDataCols->numOfRows);
-        if (tsdbWriteBlockToFile(pHelper, &(pHelper->files.lastF), pDataCols, &compBlock, true, false) < 0) return -1;
+        if (tsdbWriteBlockToFile(pHelper, helperLastF(pHelper), pDataCols, &compBlock, true, false) < 0) return -1;
         if (tsdbAddSubBlock(pHelper, &compBlock, tblkIdx, rowsRead) < 0) return -1;
         tblkIdx++;
       } else {
@@ -1466,7 +1557,7 @@ static int tsdbProcessMergeCommit(SRWHelper *pHelper, SCommitIter *pCommitIter,
         if (rowsRead == 0) break;
 
         ASSERT(rowsRead == pDataCols->numOfRows);
-        if (tsdbWriteBlockToFile(pHelper, &(pHelper->files.dataF), pDataCols, &compBlock, false, true) < 0) return -1;
+        if (tsdbWriteBlockToFile(pHelper, helperDataF(pHelper), pDataCols, &compBlock, false, true) < 0) return -1;
         if (tsdbInsertSuperBlock(pHelper, &compBlock, tblkIdx) < 0) return -1;
         tblkIdx++;
       }
@@ -1493,7 +1584,7 @@ static int tsdbProcessMergeCommit(SRWHelper *pHelper, SCommitIter *pCommitIter,
           int rowsRead = tsdbLoadDataFromCache(pTable, pCommitIter->pIter, keyLimit, rows, pDataCols,
                                                pDataCols0->cols[0].pData, pDataCols0->numOfRows);
           ASSERT(rowsRead == rows && rowsRead == pDataCols->numOfRows);
-          if (tsdbWriteBlockToFile(pHelper, &(pHelper->files.dataF), pDataCols, &compBlock, false, false) < 0)
+          if (tsdbWriteBlockToFile(pHelper, helperDataF(pHelper), pDataCols, &compBlock, false, false) < 0)
             return -1;
           if (tsdbAddSubBlock(pHelper, &compBlock, tblkIdx, rowsRead) < 0) return -1;
           tblkIdx++;
@@ -1506,7 +1597,7 @@ static int tsdbProcessMergeCommit(SRWHelper *pHelper, SCommitIter *pCommitIter,
                 tsdbLoadAndMergeFromCache(pDataCols0, &dIter, pCommitIter, pDataCols, keyLimit, defaultRowsInBlock);
             if (rowsRead == 0) break;
 
-            if (tsdbWriteBlockToFile(pHelper, &(pHelper->files.dataF), pDataCols, &compBlock, false, true) < 0)
+            if (tsdbWriteBlockToFile(pHelper, helperDataF(pHelper), pDataCols, &compBlock, false, true) < 0)
               return -1;
             if (round == 0) {
               if (tsdbUpdateSuperBlock(pHelper, &compBlock, tblkIdx) < 0) return -1;
@@ -1577,10 +1668,10 @@ static int tsdbWriteBlockToProperFile(SRWHelper *pHelper, SDataCols *pDataCols,
   ASSERT(pDataCols->numOfRows > 0);
 
   if (pDataCols->numOfRows >= pCfg->minRowsPerFileBlock) {
-    pFile = &(pHelper->files.dataF);
+    pFile = helperDataF(pHelper);
   } else {
     isLast = true;
-    pFile = TSDB_NLAST_FILE_OPENED(pHelper) ? &(pHelper->files.nLastF) : &(pHelper->files.lastF);
+    pFile = TSDB_NLAST_FILE_OPENED(pHelper) ? helperNewLastF(pHelper) : helperLastF(pHelper);
   }
 
   ASSERT(pFile->fd > 0);
diff --git a/src/tsdb/src/tsdbRead.c b/src/tsdb/src/tsdbRead.c
index 37784577c498da13f15e2489c5c1aecc38106ad6..b2204948d0232b5402a02fd7cb47b27368880893 100644
--- a/src/tsdb/src/tsdbRead.c
+++ b/src/tsdb/src/tsdbRead.c
@@ -126,12 +126,13 @@ typedef struct STsdbQueryHandle {
   SIOCostSummary cost;
 } STsdbQueryHandle;
 
-static void changeQueryHandleForLastrowQuery(TsdbQueryHandleT pqHandle);
-static void changeQueryHandleForInterpQuery(TsdbQueryHandleT pHandle);
-static void doMergeTwoLevelData(STsdbQueryHandle* pQueryHandle, STableCheckInfo* pCheckInfo, SCompBlock* pBlock);
+static void    changeQueryHandleForLastrowQuery(TsdbQueryHandleT pqHandle);
+static void    changeQueryHandleForInterpQuery(TsdbQueryHandleT pHandle);
+static void    doMergeTwoLevelData(STsdbQueryHandle* pQueryHandle, STableCheckInfo* pCheckInfo, SCompBlock* pBlock);
 static int32_t binarySearchForKey(char* pValue, int num, TSKEY key, int order);
-static int tsdbReadRowsFromCache(STableCheckInfo* pCheckInfo, TSKEY maxKey, int maxRowsToRead, STimeWindow* win,
-                                 STsdbQueryHandle* pQueryHandle);
+static int     tsdbReadRowsFromCache(STableCheckInfo* pCheckInfo, TSKEY maxKey, int maxRowsToRead, STimeWindow* win,
+                                     STsdbQueryHandle* pQueryHandle);
+static int     tsdbCheckInfoCompar(const void* key1, const void* key2);
 
 static void tsdbInitDataBlockLoadInfo(SDataBlockLoadInfo* pBlockLoadInfo) {
   pBlockLoadInfo->slot = -1;
@@ -236,7 +237,8 @@ TsdbQueryHandleT* tsdbQueryTables(TSDB_REPO_T* tsdb, STsdbQueryCond* pCond, STab
       taosArrayPush(pQueryHandle->pTableCheckInfo, &info);
     }
   }
-
+  
+  taosArraySort(pQueryHandle->pTableCheckInfo, tsdbCheckInfoCompar);
   pQueryHandle->defaultLoadColumn = getDefaultLoadColumns(pQueryHandle, true);
 
   tsdbDebug("%p total numOfTable:%zu in query, %p", pQueryHandle, taosArrayGetSize(pQueryHandle->pTableCheckInfo), pQueryHandle->qinfo);
@@ -554,7 +556,9 @@ static int32_t getFileCompInfo(STsdbQueryHandle* pQueryHandle, int32_t* numOfBlo
     STableCheckInfo* pCheckInfo = taosArrayGet(pQueryHandle->pTableCheckInfo, i);
     pCheckInfo->numOfBlocks = 0;
 
-    SCompIdx* compIndex = &pQueryHandle->rhelper.pCompIdx[pCheckInfo->tableId.tid];
+    tsdbSetHelperTable(&pQueryHandle->rhelper, pCheckInfo->pTableObj, pQueryHandle->pTsdb);
+
+    SCompIdx* compIndex = &pQueryHandle->rhelper.curCompIdx;
 
     // no data block in this file, try next file
     if (compIndex->len == 0 || compIndex->numOfBlocks == 0 || compIndex->uid != pCheckInfo->tableId.uid) {
@@ -571,8 +575,6 @@ static int32_t getFileCompInfo(STsdbQueryHandle* pQueryHandle, int32_t* numOfBlo
       pCheckInfo->compSize = compIndex->len;
     }
 
-    tsdbSetHelperTable(&pQueryHandle->rhelper, pCheckInfo->pTableObj, pQueryHandle->pTsdb);
-
     tsdbLoadCompInfo(&(pQueryHandle->rhelper), (void *)(pCheckInfo->pCompInfo));
     SCompInfo* pCompInfo = pCheckInfo->pCompInfo;
 
@@ -2431,3 +2433,13 @@ void tsdbDestroyTableGroup(STableGroupInfo *pGroupList) {
   taosArrayDestroy(pGroupList->pGroupList);
 }
 
+static int tsdbCheckInfoCompar(const void* key1, const void* key2) {
+  if (((STableCheckInfo*)key1)->tableId.tid < ((STableCheckInfo*)key2)->tableId.tid) {
+    return -1;
+  } else if (((STableCheckInfo*)key1)->tableId.tid > ((STableCheckInfo*)key2)->tableId.tid) {
+    return 1;
+  } else {
+    ASSERT(false);
+    return 0;
+  }
+}
\ No newline at end of file
diff --git a/src/util/inc/tkvstore.h b/src/util/inc/tkvstore.h
index 346e567c41e0a209b7dde96de55faa74a704f9b3..6d67607e24113771e09d2f8707ae5930fb21b20a 100644
--- a/src/util/inc/tkvstore.h
+++ b/src/util/inc/tkvstore.h
@@ -25,10 +25,11 @@ typedef int (*iterFunc)(void *, void *cont, int contLen);
 typedef void (*afterFunc)(void *);
 
 typedef struct {
-  int64_t size;  // including 512 bytes of header size
-  int64_t tombSize;
-  int64_t nRecords;
-  int64_t nDels;
+  int64_t  size;  // including 512 bytes of header size
+  int64_t  tombSize;
+  int64_t  nRecords;
+  int64_t  nDels;
+  uint32_t magic;
 } SStoreInfo;
 
 typedef struct {
@@ -45,6 +46,8 @@ typedef struct {
   SStoreInfo info;
 } SKVStore;
 
+#define KVSTORE_MAGIC(s) (s)->info.magic
+
 int       tdCreateKVStore(char *fname);
 int       tdDestroyKVStore(char *fname);
 SKVStore *tdOpenKVStore(char *fname, iterFunc iFunc, afterFunc aFunc, void *appH);
diff --git a/src/util/src/tkvstore.c b/src/util/src/tkvstore.c
index ab2aa738c66b68684883a0f02a59bba4a5b90667..0704285da5fd1cc390c11891e2983c32ed5f5265 100644
--- a/src/util/src/tkvstore.c
+++ b/src/util/src/tkvstore.c
@@ -34,6 +34,7 @@
 #define TD_KVSTORE_MAINOR_VERSION 0
 #define TD_KVSTORE_SNAP_SUFFIX ".snap"
 #define TD_KVSTORE_NEW_SUFFIX ".new"
+#define TD_KVSTORE_INIT_MAGIC 0xFFFFFFFF
 
 typedef struct {
   uint64_t uid;
@@ -140,6 +141,7 @@ SKVStore *tdOpenKVStore(char *fname, iterFunc iFunc, afterFunc aFunc, void *appH
   if (tdLoadKVStoreHeader(pStore->fd, pStore->fname, &info) < 0) goto _err;
 
   pStore->info.size = TD_KVSTORE_HEADER_SIZE;
+  pStore->info.magic = info.magic;
 
   if (tdRestoreKVStore(pStore) < 0) goto _err;
 
@@ -251,6 +253,8 @@ int tdUpdateKVStoreRecord(SKVStore *pStore, uint64_t uid, void *cont, int contLe
     return -1;
   }
 
+  pStore->info.magic =
+      taosCalcChecksum(pStore->info.magic, (uint8_t *)POINTER_SHIFT(cont, contLen - sizeof(TSCKSUM)), sizeof(TSCKSUM));
   pStore->info.size += (sizeof(SKVRecord) + contLen);
   SKVRecord *pRecord = taosHashGet(pStore->map, (void *)&uid, sizeof(uid));
   if (pRecord != NULL) {  // just to insert
@@ -288,6 +292,7 @@ int tdDropKVStoreRecord(SKVStore *pStore, uint64_t uid) {
     return -1;
   }
 
+  pStore->info.magic = taosCalcChecksum(pStore->info.magic, (uint8_t *)buf, POINTER_DISTANCE(pBuf, buf));
   pStore->info.size += POINTER_DISTANCE(pBuf, buf);
   pStore->info.nDels++;
   pStore->info.nRecords--;
@@ -371,7 +376,7 @@ static int tdUpdateKVStoreHeader(int fd, char *fname, SStoreInfo *pInfo) {
 }
 
 static int tdInitKVStoreHeader(int fd, char *fname) {
-  SStoreInfo info = {TD_KVSTORE_HEADER_SIZE, 0, 0, 0};
+  SStoreInfo info = {TD_KVSTORE_HEADER_SIZE, 0, 0, 0, TD_KVSTORE_INIT_MAGIC};
 
   return tdUpdateKVStoreHeader(fd, fname, &info);
 }
@@ -382,6 +387,7 @@ static int tdEncodeStoreInfo(void **buf, SStoreInfo *pInfo) {
   tlen += taosEncodeVariantI64(buf, pInfo->tombSize);
   tlen += taosEncodeVariantI64(buf, pInfo->nRecords);
   tlen += taosEncodeVariantI64(buf, pInfo->nDels);
+  tlen += taosEncodeFixedU32(buf, pInfo->magic);
 
   return tlen;
 }
@@ -391,6 +397,7 @@ static void *tdDecodeStoreInfo(void *buf, SStoreInfo *pInfo) {
   buf = taosDecodeVariantI64(buf, &(pInfo->tombSize));
   buf = taosDecodeVariantI64(buf, &(pInfo->nRecords));
   buf = taosDecodeVariantI64(buf, &(pInfo->nDels));
+  buf = taosDecodeFixedU32(buf, &(pInfo->magic));
 
   return buf;
 }
diff --git a/tests/pytest/fulltest.sh b/tests/pytest/fulltest.sh
index 9d1aef0dc5cc2cf266931ff6e8ba88794649686c..904e712fa46a9f409d8196759569b22c84a091b6 100755
--- a/tests/pytest/fulltest.sh
+++ b/tests/pytest/fulltest.sh
@@ -144,6 +144,7 @@ python3 ./test.py -f query/querySort.py
 python3 ./test.py -f query/queryJoin.py
 python3 ./test.py -f query/select_last_crash.py
 python3 ./test.py -f query/queryNullValueTest.py
+python3 ./test.py -f query/queryInsertValue.py
 
 #stream
 python3 ./test.py -f stream/metric_1.py
@@ -161,3 +162,22 @@ python3 ./test.py -f client/client.py
 # Misc
 python3 testCompress.py
 python3 testNoCompress.py
+
+# functions
+python3 ./test.py -f functions/function_avg.py
+python3 ./test.py -f functions/function_bottom.py
+python3 ./test.py -f functions/function_count.py
+python3 ./test.py -f functions/function_diff.py
+python3 ./test.py -f functions/function_first.py
+python3 ./test.py -f functions/function_last.py
+python3 ./test.py -f functions/function_last_row.py
+python3 ./test.py -f functions/function_leastsquares.py
+python3 ./test.py -f functions/function_max.py
+python3 ./test.py -f functions/function_min.py
+python3 ./test.py -f functions/function_operations.py
+python3 ./test.py -f functions/function_percentile.py
+python3 ./test.py -f functions/function_spread.py
+python3 ./test.py -f functions/function_stddev.py
+python3 ./test.py -f functions/function_sum.py
+python3 ./test.py -f functions/function_top.py
+python3 ./test.py -f functions/function_twa.py
\ No newline at end of file
diff --git a/tests/pytest/functions/function_avg.py b/tests/pytest/functions/function_avg.py
new file mode 100644
index 0000000000000000000000000000000000000000..9481550ba3f9d912b734d19b7c794c495fffdecd
--- /dev/null
+++ b/tests/pytest/functions/function_avg.py
@@ -0,0 +1,73 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # average verifacation 
+        tdSql.error("select avg(ts) from test")
+        tdSql.error("select avg(ts) from test1")
+        tdSql.error("select avg(col7) from test")
+        tdSql.error("select avg(col7) from test1")
+        tdSql.error("select avg(col8) from test")
+        tdSql.error("select avg(col8) from test1")
+        tdSql.error("select avg(col9) from test")
+        tdSql.error("select avg(col9) from test1")
+
+        tdSql.query("select avg(col1) from test")
+        tdSql.checkData(0, 0, np.average(intData))
+        tdSql.query("select avg(col2) from test")
+        tdSql.checkData(0, 0, np.average(intData))
+        tdSql.query("select avg(col3) from test")
+        tdSql.checkData(0, 0, np.average(intData))
+        tdSql.query("select avg(col4) from test")
+        tdSql.checkData(0, 0, np.average(intData))
+        tdSql.query("select avg(col5) from test")
+        tdSql.checkData(0, 0, np.average(floatData))              
+        tdSql.query("select avg(col6) from test")
+        tdSql.checkData(0, 0, np.average(floatData))              
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_bottom.py b/tests/pytest/functions/function_bottom.py
new file mode 100644
index 0000000000000000000000000000000000000000..4074166f927acbbcbb5899a692ff87f3c187f92f
--- /dev/null
+++ b/tests/pytest/functions/function_bottom.py
@@ -0,0 +1,93 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()    
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))                            
+
+        # bottom verifacation 
+        tdSql.error("select bottom(ts, 10) from test")
+        tdSql.error("select bottom(col1, 0) from test")
+        tdSql.error("select bottom(col1, 101) from test")
+        tdSql.error("select bottom(col2, 0) from test")
+        tdSql.error("select bottom(col2, 101) from test")
+        tdSql.error("select bottom(col3, 0) from test")
+        tdSql.error("select bottom(col3, 101) from test")
+        tdSql.error("select bottom(col4, 0) from test")
+        tdSql.error("select bottom(col4, 101) from test")
+        tdSql.error("select bottom(col5, 0) from test")
+        tdSql.error("select bottom(col5, 101) from test")
+        tdSql.error("select bottom(col6, 0) from test")
+        tdSql.error("select bottom(col6, 101) from test")        
+        tdSql.error("select bottom(col7, 10) from test")        
+        tdSql.error("select bottom(col8, 10) from test")
+        tdSql.error("select bottom(col9, 10) from test")
+
+        tdSql.query("select bottom(col1, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 1)
+        tdSql.checkData(1, 1, 2)
+
+        tdSql.query("select bottom(col2, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 1)
+        tdSql.checkData(1, 1, 2)
+
+        tdSql.query("select bottom(col3, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 1)
+        tdSql.checkData(1, 1, 2)
+
+        tdSql.query("select bottom(col4, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 1)
+        tdSql.checkData(1, 1, 2)
+
+        tdSql.query("select bottom(col5, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 0.1)
+        tdSql.checkData(1, 1, 1.1)
+
+        tdSql.query("select bottom(col6, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 0.1)
+        tdSql.checkData(1, 1, 1.1)
+                   
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_count.py b/tests/pytest/functions/function_count.py
new file mode 100644
index 0000000000000000000000000000000000000000..4795a6b2dfe72bb9fa747b550be9f56c0c255d88
--- /dev/null
+++ b/tests/pytest/functions/function_count.py
@@ -0,0 +1,79 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+        
+        # Count verifacation
+        tdSql.query("select count(*) from test")        
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select count(ts) from test")        
+        tdSql.checkData(0, 0, 10)                        
+        tdSql.query("select count(col1) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col2) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col3) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col4) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col5) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col6) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col7) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col8) from test")        
+        tdSql.checkData(0, 0, 10)
+        tdSql.query("select count(col9) from test")        
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.execute("alter table test add column col10 int")
+        tdSql.query("select count(col10) from test")        
+        tdSql.checkRows(0)
+
+        tdSql.execute("insert into test1 values(now, 1, 2, 3, 4, 1.1, 2.2, false, 'test', 'test' 1)")
+        tdSql.query("select count(col10) from test")        
+        tdSql.checkData(0, 0, 1)        
+              
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_diff.py b/tests/pytest/functions/function_diff.py
new file mode 100644
index 0000000000000000000000000000000000000000..b6f496d7d68ebaa0f19dfc947d7745802198a3dc
--- /dev/null
+++ b/tests/pytest/functions/function_diff.py
@@ -0,0 +1,99 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        tdSql.execute("insert into test1 values(%d, 0, 0, 0, 0, 0.0, 0.0, False, ' ', ' ')" % (self.ts - 1))
+        
+        # diff verifacation 
+        tdSql.query("select diff(col1) from test1")
+        tdSql.checkRows(0)
+        
+        tdSql.query("select diff(col2) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select diff(col3) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select diff(col4) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select diff(col5) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select diff(col6) from test1")
+        tdSql.checkRows(0)
+
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))                                
+        
+        tdSql.error("select diff(ts) from test")
+        tdSql.error("select diff(ts) from test1")
+        tdSql.error("select diff(col1) from test")
+        tdSql.error("select diff(col2) from test")
+        tdSql.error("select diff(col3) from test")
+        tdSql.error("select diff(col4) from test")
+        tdSql.error("select diff(col5) from test")
+        tdSql.error("select diff(col6) from test")
+        tdSql.error("select diff(col7) from test")     
+        tdSql.error("select diff(col7) from test1")               
+        tdSql.error("select diff(col8) from test") 
+        tdSql.error("select diff(col8) from test1")
+        tdSql.error("select diff(col9) from test")        
+        tdSql.error("select diff(col9) from test1")
+        
+        tdSql.query("select diff(col1) from test1")
+        tdSql.checkRows(10)
+
+        tdSql.query("select diff(col2) from test1")
+        tdSql.checkRows(10)
+
+        tdSql.query("select diff(col3) from test1")
+        tdSql.checkRows(10)
+
+        tdSql.query("select diff(col4) from test1")
+        tdSql.checkRows(10)
+
+        tdSql.query("select diff(col5) from test1")
+        tdSql.checkRows(10)
+
+        tdSql.query("select diff(col6) from test1")
+        tdSql.checkRows(10)
+        
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_first.py b/tests/pytest/functions/function_first.py
new file mode 100644
index 0000000000000000000000000000000000000000..2b78bd33d8bdb0bcd6775215b1cf0b1e398f2928
--- /dev/null
+++ b/tests/pytest/functions/function_first.py
@@ -0,0 +1,119 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        tdSql.execute("insert into test1(ts) values(%d)" % (self.ts - 1))
+
+        # first verifacation         
+        tdSql.query("select first(*) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 1, None)
+
+        tdSql.query("select first(col1) from test1")
+        tdSql.checkRows(0)        
+
+        tdSql.query("select first(col2) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select first(col3) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select first(col4) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select first(col5) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select first(col6) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select first(col7) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select first(col8) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select first(col9) from test1")
+        tdSql.checkRows(0)
+
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))            
+
+        tdSql.query("select first(*) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 1, 1)
+
+        tdSql.query("select first(col1) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 1)
+
+        tdSql.query("select first(col2) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 1)
+
+        tdSql.query("select first(col3) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 1)
+
+        tdSql.query("select first(col4) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 1)
+
+        tdSql.query("select first(col5) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0.1)
+
+        tdSql.query("select first(col6) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0.1)
+
+        tdSql.query("select first(col7) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, False)
+
+        tdSql.query("select first(col8) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 'taosdata1')
+
+        tdSql.query("select first(col9) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, '涛思数据1')
+                
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_last.py b/tests/pytest/functions/function_last.py
new file mode 100644
index 0000000000000000000000000000000000000000..337c18a28c2cd99d556e5b017377edc56671c490
--- /dev/null
+++ b/tests/pytest/functions/function_last.py
@@ -0,0 +1,119 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        tdSql.execute("insert into test1(ts) values(%d)" % (self.ts - 1))
+
+        # last verifacation         
+        tdSql.query("select last(*) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 1, None)
+
+        tdSql.query("select last(col1) from test1")
+        tdSql.checkRows(0)        
+
+        tdSql.query("select last(col2) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select last(col3) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select last(col4) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select last(col5) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select last(col6) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select last(col7) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select last(col8) from test1")
+        tdSql.checkRows(0)
+
+        tdSql.query("select last(col9) from test1")
+        tdSql.checkRows(0)
+
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))            
+
+        tdSql.query("select last(*) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 1, 10)
+
+        tdSql.query("select last(col1) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last(col2) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last(col3) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last(col4) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last(col5) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+
+        tdSql.query("select last(col6) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+
+        tdSql.query("select last(col7) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, True)
+
+        tdSql.query("select last(col8) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 'taosdata10')
+
+        tdSql.query("select last(col9) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, '涛思数据10')
+                
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_last_row.py b/tests/pytest/functions/function_last_row.py
new file mode 100644
index 0000000000000000000000000000000000000000..ea5cf661eb9e70e2ed06ebd712b2f65dfa62beeb
--- /dev/null
+++ b/tests/pytest/functions/function_last_row.py
@@ -0,0 +1,128 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        tdSql.execute("insert into test1(ts) values(%d)" % (self.ts - 1))
+
+        # last_row verifacation         
+        tdSql.query("select last_row(*) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 1, None)
+
+        tdSql.query("select last_row(col1) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col2) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col3) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col4) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col5) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col6) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col7) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col8) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        tdSql.query("select last_row(col9) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, None)
+
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))              
+
+        tdSql.query("select last_row(*) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 1, 10)
+
+        tdSql.query("select last_row(col1) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last_row(col2) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last_row(col3) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last_row(col4) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select last_row(col5) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+
+        tdSql.query("select last_row(col6) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+
+        tdSql.query("select last_row(col7) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, True)
+
+        tdSql.query("select last_row(col8) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 'taosdata10')
+
+        tdSql.query("select last_row(col9) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, '涛思数据10')
+                
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_leastsquares.py b/tests/pytest/functions/function_leastsquares.py
new file mode 100644
index 0000000000000000000000000000000000000000..0ef0a2b78612dca604f7a7a7f70841c917376a17
--- /dev/null
+++ b/tests/pytest/functions/function_leastsquares.py
@@ -0,0 +1,75 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))                                   
+
+        # leastsquares verifacation 
+        tdSql.error("select leastsquares(ts, 1, 1) from test1")
+        tdSql.error("select leastsquares(col1, 1, 1) from test")
+        tdSql.error("select leastsquares(col2, 1, 1) from test")
+        tdSql.error("select leastsquares(col3, 1, 1) from test")
+        tdSql.error("select leastsquares(col4, 1, 1) from test")
+        tdSql.error("select leastsquares(col5, 1, 1) from test")
+        tdSql.error("select leastsquares(col6, 1, 1) from test")
+        tdSql.error("select leastsquares(col7, 1, 1) from test1")
+        tdSql.error("select leastsquares(col8, 1, 1) from test1")
+        tdSql.error("select leastsquares(col9, 1, 1) from test1")
+                
+        tdSql.query("select leastsquares(col1, 1, 1) from test1")
+        tdSql.checkData(0, 0, '{slop:1.000000, intercept:0.000000}')
+
+        tdSql.query("select leastsquares(col2, 1, 1) from test1")
+        tdSql.checkData(0, 0, '{slop:1.000000, intercept:0.000000}')
+
+        tdSql.query("select leastsquares(col3, 1, 1) from test1")
+        tdSql.checkData(0, 0, '{slop:1.000000, intercept:0.000000}')
+
+        tdSql.query("select leastsquares(col4, 1, 1) from test1")
+        tdSql.checkData(0, 0, '{slop:1.000000, intercept:0.000000}')
+
+        tdSql.query("select leastsquares(col5, 1, 1) from test1")
+        tdSql.checkData(0, 0, '{slop:1.000000, intercept:-0.900000}')
+
+        tdSql.query("select leastsquares(col6, 1, 1) from test1")
+        tdSql.checkData(0, 0, '{slop:1.000000, intercept:-0.900000}')
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_max.py b/tests/pytest/functions/function_max.py
new file mode 100644
index 0000000000000000000000000000000000000000..3bd5031276adfd76574a1a43e311a1d6ec81ab16
--- /dev/null
+++ b/tests/pytest/functions/function_max.py
@@ -0,0 +1,78 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # max verifacation 
+        tdSql.error("select max(ts) from test")
+        tdSql.error("select max(ts) from test1")
+        tdSql.error("select max(col7) from test")
+        tdSql.error("select max(col7) from test1")
+        tdSql.error("select max(col8) from test")
+        tdSql.error("select max(col8) from test1")
+        tdSql.error("select max(col9) from test")
+        tdSql.error("select max(col9) from test1")
+        
+        tdSql.query("select max(col1) from test1")
+        tdSql.checkData(0, 0, np.max(intData))
+
+        tdSql.query("select max(col2) from test1")
+        tdSql.checkData(0, 0, np.max(intData))
+
+        tdSql.query("select max(col3) from test1")
+        tdSql.checkData(0, 0, np.max(intData))
+
+        tdSql.query("select max(col4) from test1")
+        tdSql.checkData(0, 0, np.max(intData))
+        
+        tdSql.query("select max(col5) from test1")
+        tdSql.checkData(0, 0, np.max(floatData))
+
+        tdSql.query("select max(col6) from test1")
+        tdSql.checkData(0, 0, np.max(floatData))
+        
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_min.py b/tests/pytest/functions/function_min.py
new file mode 100644
index 0000000000000000000000000000000000000000..bc180bc22414a4a3aa3d233438b10a04fd08bc2b
--- /dev/null
+++ b/tests/pytest/functions/function_min.py
@@ -0,0 +1,78 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # min verifacation 
+        tdSql.error("select min(ts) from test")
+        tdSql.error("select min(ts) from test1")
+        tdSql.error("select min(col7) from test")
+        tdSql.error("select min(col7) from test1")
+        tdSql.error("select min(col8) from test")
+        tdSql.error("select min(col8) from test1")
+        tdSql.error("select min(col9) from test")
+        tdSql.error("select min(col9) from test1")
+        
+        tdSql.query("select min(col1) from test1")
+        tdSql.checkData(0, 0, np.min(intData))
+
+        tdSql.query("select min(col2) from test1")
+        tdSql.checkData(0, 0, np.min(intData))
+
+        tdSql.query("select min(col3) from test1")
+        tdSql.checkData(0, 0, np.min(intData))
+
+        tdSql.query("select min(col4) from test1")
+        tdSql.checkData(0, 0, np.min(intData))
+        
+        tdSql.query("select min(col5) from test1")
+        tdSql.checkData(0, 0, np.min(floatData))
+
+        tdSql.query("select min(col6) from test1")
+        tdSql.checkData(0, 0, np.min(floatData))
+        
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_operations.py b/tests/pytest/functions/function_operations.py
new file mode 100644
index 0000000000000000000000000000000000000000..36810621cb2adac494f2c3332c13f31b8ff69962
--- /dev/null
+++ b/tests/pytest/functions/function_operations.py
@@ -0,0 +1,81 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))                       
+
+        # min verifacation 
+        tdSql.error("select ts + col1 from test")
+        tdSql.error("select ts + col1 from test1")
+        tdSql.error("select col1 + col7 from test")
+        tdSql.error("select col1 + col7 from test1")
+        tdSql.error("select col1 + col8 from test")
+        tdSql.error("select col1 + col8 from test1")
+        tdSql.error("select col1 + col9 from test")
+        tdSql.error("select col1 + col9 from test1")
+
+        tdSql.query("select col1 + col2 from test1")
+        tdSql.checkRows(10)
+        tdSql.checkData(0, 0, 2.0)
+        
+        tdSql.query("select col1 + col2 * col3 from test1")
+        tdSql.checkRows(10)
+        tdSql.checkData(1, 0, 6.0)
+
+        tdSql.query("select col1 + col2 * col3 + col3 / col4 + col5 + col6 from test1")
+        tdSql.checkRows(10)
+        tdSql.checkData(0, 0, 3.2)
+
+        tdSql.execute("insert into test1(ts, col1) values(%d, 11)" % (self.ts + 11))
+        tdSql.query("select col1 + col2 from test1")
+        tdSql.checkRows(11)
+        tdSql.checkData(10, 0, None)
+        
+        tdSql.query("select col1 + col2 * col3 from test1")
+        tdSql.checkRows(11)
+        tdSql.checkData(10, 0, None)
+
+        tdSql.query("select col1 + col2 * col3 + col3 / col4 + col5 + col6 from test1")
+        tdSql.checkRows(11)
+        tdSql.checkData(10, 0, None)
+
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_percentile.py b/tests/pytest/functions/function_percentile.py
new file mode 100644
index 0000000000000000000000000000000000000000..aaeb94372e44282da0d83849c18e40857463b42c
--- /dev/null
+++ b/tests/pytest/functions/function_percentile.py
@@ -0,0 +1,140 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20))''')
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # percentile verifacation 
+        tdSql.error("select percentile(ts 20) from test")
+        tdSql.error("select apercentile(ts 20) from test")
+        tdSql.error("select percentile(col7 20) from test")
+        tdSql.error("select apercentile(col7 20) from test")
+        tdSql.error("select percentile(col8 20) from test")        
+        tdSql.error("select apercentile(col8 20) from test")
+        tdSql.error("select percentile(col9 20) from test")
+        tdSql.error("select apercentile(col9 20) from test")        
+
+        tdSql.query("select percentile(col1, 0) from test")        
+        tdSql.checkData(0, 0, np.percentile(intData, 0))
+        tdSql.query("select apercentile(col1, 0) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col1, 50) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 50))
+        tdSql.query("select apercentile(col1, 50) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col1, 100) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 100))
+        tdSql.query("select apercentile(col1, 100) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))  
+
+        tdSql.query("select percentile(col2, 0) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 0))
+        tdSql.query("select apercentile(col2, 0) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col2, 50) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 50))
+        tdSql.query("select apercentile(col2, 50) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col2, 100) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 100)) 
+        tdSql.query("select apercentile(col2, 100) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+
+        tdSql.query("select percentile(col3, 0) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 0))
+        tdSql.query("select apercentile(col3, 0) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col3, 50) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 50))
+        tdSql.query("select apercentile(col3, 50) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col3, 100) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 100))
+        tdSql.query("select apercentile(col3, 100) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+
+        tdSql.query("select percentile(col4, 0) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 0))
+        tdSql.query("select apercentile(col4, 0) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col4, 50) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 50))
+        tdSql.query("select apercentile(col4, 50) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col4, 100) from test")
+        tdSql.checkData(0, 0, np.percentile(intData, 100)) 
+        tdSql.query("select apercentile(col4, 100) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+
+        tdSql.query("select percentile(col5, 0) from test")        
+        print("query result: %s" % tdSql.getData(0, 0))
+        print("array result: %s" % np.percentile(floatData, 0))
+        tdSql.query("select apercentile(col5, 0) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col5, 50) from test")
+        print("query result: %s" % tdSql.getData(0, 0))
+        print("array result: %s" % np.percentile(floatData, 50))
+        tdSql.query("select apercentile(col5, 50) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))        
+        tdSql.query("select percentile(col5, 100) from test")
+        print("query result: %s" % tdSql.getData(0, 0))
+        print("array result: %s" % np.percentile(floatData, 100)) 
+        tdSql.query("select apercentile(col5, 100) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))     
+
+        tdSql.query("select percentile(col6, 0) from test")
+        tdSql.checkData(0, 0, np.percentile(floatData, 0))
+        tdSql.query("select apercentile(col6, 0) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col6, 50) from test")
+        tdSql.checkData(0, 0, np.percentile(floatData, 50))
+        tdSql.query("select apercentile(col6, 50) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))
+        tdSql.query("select percentile(col6, 100) from test")
+        tdSql.checkData(0, 0, np.percentile(floatData, 100)) 
+        tdSql.query("select apercentile(col6, 100) from test")
+        print("apercentile result: %s" % tdSql.getData(0, 0))       
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_spread.py b/tests/pytest/functions/function_spread.py
new file mode 100644
index 0000000000000000000000000000000000000000..462933597388090f069f9319751aaea032ea4133
--- /dev/null
+++ b/tests/pytest/functions/function_spread.py
@@ -0,0 +1,106 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()        
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        tdSql.execute("insert into test1 values(%d, 0, 0, 0, 0, 0.0, 0.0, False, ' ', ' ')" % (self.ts - 1))
+        
+        # spread verifacation 
+        tdSql.query("select spread(ts) from test1")
+        tdSql.checkRows(1)       
+
+        tdSql.query("select spread(col1) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0)
+
+        tdSql.query("select spread(col2) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0)
+
+        tdSql.query("select spread(col3) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0)
+
+        tdSql.query("select spread(col4) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0)
+
+        tdSql.query("select spread(col5) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0)
+
+        tdSql.query("select spread(col6) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 0)
+
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))                                  
+       
+        tdSql.error("select spread(col7) from test")     
+        tdSql.error("select spread(col7) from test1")               
+        tdSql.error("select spread(col8) from test") 
+        tdSql.error("select spread(col8) from test1")
+        tdSql.error("select spread(col9) from test")        
+        tdSql.error("select spread(col9) from test1")
+        
+        tdSql.query("select spread(col1) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select spread(col2) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select spread(col3) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select spread(col4) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 10)
+
+        tdSql.query("select spread(col5) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+
+        tdSql.query("select spread(col6) from test1")
+        tdSql.checkRows(1)
+        tdSql.checkData(0, 0, 9.1)
+        
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_stddev.py b/tests/pytest/functions/function_stddev.py
new file mode 100644
index 0000000000000000000000000000000000000000..23df415aa35feecf84ba40a50604d2b86fc7f008
--- /dev/null
+++ b/tests/pytest/functions/function_stddev.py
@@ -0,0 +1,80 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # stddev verifacation 
+        tdSql.error("select stddev(ts) from test1")
+        tdSql.error("select stddev(col1) from test")
+        tdSql.error("select stddev(col2) from test")
+        tdSql.error("select stddev(col3) from test")
+        tdSql.error("select stddev(col4) from test")
+        tdSql.error("select stddev(col5) from test")
+        tdSql.error("select stddev(col6) from test")
+        tdSql.error("select stddev(col7) from test1")
+        tdSql.error("select stddev(col8) from test1")
+        tdSql.error("select stddev(col9) from test1")
+
+        tdSql.query("select stddev(col1) from test1")
+        tdSql.checkData(0, 0, np.std(intData))
+
+        tdSql.query("select stddev(col2) from test1")
+        tdSql.checkData(0, 0, np.std(intData))
+
+        tdSql.query("select stddev(col3) from test1")
+        tdSql.checkData(0, 0, np.std(intData))
+
+        tdSql.query("select stddev(col4) from test1")
+        tdSql.checkData(0, 0, np.std(intData))
+
+        tdSql.query("select stddev(col5) from test1")
+        tdSql.checkData(0, 0, np.std(floatData))
+
+        tdSql.query("select stddev(col6) from test1")
+        tdSql.checkData(0, 0, np.std(floatData))
+            
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_sum.py b/tests/pytest/functions/function_sum.py
new file mode 100644
index 0000000000000000000000000000000000000000..ef5ddfe3158cc3c3072fb474bdc42d50a8de30f0
--- /dev/null
+++ b/tests/pytest/functions/function_sum.py
@@ -0,0 +1,69 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # sum verifacation 
+        tdSql.error("select sum(ts) from test")
+        tdSql.error("select sum(col7) from test")
+        tdSql.error("select sum(col8) from test")
+        tdSql.error("select sum(col9) from test")
+
+        tdSql.query("select sum(col1) from test")
+        tdSql.checkData(0, 0, np.sum(intData))
+        tdSql.query("select sum(col2) from test")
+        tdSql.checkData(0, 0, np.sum(intData))
+        tdSql.query("select sum(col3) from test")
+        tdSql.checkData(0, 0, np.sum(intData))
+        tdSql.query("select sum(col4) from test")
+        tdSql.checkData(0, 0, np.sum(intData))
+        tdSql.query("select sum(col5) from test")
+        tdSql.checkData(0, 0, np.sum(floatData)) 
+        tdSql.query("select sum(col6) from test")
+        tdSql.checkData(0, 0, np.sum(floatData))              
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_top.py b/tests/pytest/functions/function_top.py
new file mode 100644
index 0000000000000000000000000000000000000000..e24ff1cc5339c79e1a87653e9b528ec34f3c2ea9
--- /dev/null
+++ b/tests/pytest/functions/function_top.py
@@ -0,0 +1,98 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # top verifacation 
+        tdSql.error("select top(ts, 10) from test")
+        tdSql.error("select top(col1, 0) from test")
+        tdSql.error("select top(col1, 101) from test")
+        tdSql.error("select top(col2, 0) from test")
+        tdSql.error("select top(col2, 101) from test")
+        tdSql.error("select top(col3, 0) from test")
+        tdSql.error("select top(col3, 101) from test")
+        tdSql.error("select top(col4, 0) from test")
+        tdSql.error("select top(col4, 101) from test")
+        tdSql.error("select top(col5, 0) from test")
+        tdSql.error("select top(col5, 101) from test")
+        tdSql.error("select top(col6, 0) from test")
+        tdSql.error("select top(col6, 101) from test")        
+        tdSql.error("select top(col7, 10) from test")        
+        tdSql.error("select top(col8, 10) from test")
+        tdSql.error("select top(col9, 10) from test")
+
+        tdSql.query("select top(col1, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 9)
+        tdSql.checkData(1, 1, 10)
+
+        tdSql.query("select top(col2, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 9)
+        tdSql.checkData(1, 1, 10)
+
+        tdSql.query("select top(col3, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 9)
+        tdSql.checkData(1, 1, 10)
+
+        tdSql.query("select top(col4, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 9)
+        tdSql.checkData(1, 1, 10)
+
+        tdSql.query("select top(col5, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 8.1)
+        tdSql.checkData(1, 1, 9.1)
+
+        tdSql.query("select top(col6, 2) from test")
+        tdSql.checkRows(2)
+        tdSql.checkData(0, 1, 8.1)
+        tdSql.checkData(1, 1, 9.1)
+                   
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/functions/function_twa.py b/tests/pytest/functions/function_twa.py
new file mode 100644
index 0000000000000000000000000000000000000000..1ce4c99b6041e2cfd6bccdbc0e00e5fd8037f9d9
--- /dev/null
+++ b/tests/pytest/functions/function_twa.py
@@ -0,0 +1,135 @@
+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+import taos
+from util.log import *
+from util.cases import *
+from util.sql import *
+import numpy as np
+
+
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor())
+
+        self.rowNum = 10
+        self.ts = 1537146000000
+        
+    def run(self):
+        tdSql.prepare()
+
+        intData = []        
+        floatData = []
+
+        tdSql.execute('''create table test(ts timestamp, col1 tinyint, col2 smallint, col3 int, col4 bigint, col5 float, col6 double, 
+                    col7 bool, col8 binary(20), col9 nchar(20)) tags(loc nchar(20))''')
+        tdSql.execute("create table test1 using test tags('beijing')")
+        for i in range(self.rowNum):
+            tdSql.execute("insert into test1 values(%d, %d, %d, %d, %d, %f, %f, %d, 'taosdata%d', '涛思数据%d')" 
+                        % (self.ts + i, i + 1, i + 1, i + 1, i + 1, i + 0.1, i + 0.1, i % 2, i + 1, i + 1))
+            intData.append(i + 1)            
+            floatData.append(i + 0.1)                        
+
+        # twa verifacation 
+        tdSql.error("select twa(ts) from test")
+        tdSql.error("select twa(ts) from test1")
+
+        tdSql.error("select twa(col1) from test")
+        tdSql.error("select twa(col1) from test1")
+
+        tdSql.error("select twa(col2) from test")
+        tdSql.error("select twa(col2) from test1")
+
+        tdSql.error("select twa(col3) from test")
+        tdSql.error("select twa(col3) from test1")
+
+        tdSql.error("select twa(col4) from test")
+        tdSql.error("select twa(col4) from test1")
+
+        tdSql.error("select twa(col5) from test")
+        tdSql.error("select twa(col5) from test1")
+
+        tdSql.error("select twa(col6) from test")
+        tdSql.error("select twa(col6) from test1")        
+
+        tdSql.error("select twa(col7) from test")
+        tdSql.error("select twa(col7) from test1")
+
+        tdSql.error("select twa(col8) from test")
+        tdSql.error("select twa(col8) from test1")
+
+        tdSql.error("select twa(col9) from test")
+        tdSql.error("select twa(col9) from test1")
+
+        tdSql.error("select twa(col1) from test where ts > %d" % self.ts)
+        tdSql.error("select twa(col1) from test1 where ts > %d" % self.ts)
+
+        tdSql.error("select twa(col2) from test where ts > %d" % self.ts)
+        tdSql.error("select twa(col2) from test1 where ts > %d" % self.ts)
+
+        tdSql.error("select twa(col3) from test where ts > %d" % self.ts)
+        tdSql.error("select twa(col3) from test1 where ts > %d" % self.ts)
+
+        tdSql.error("select twa(col4) from test where ts > %d" % self.ts)
+        tdSql.error("select twa(col4) from test1 where ts > %d" % self.ts)
+            
+        tdSql.error("select twa(col5) from test where ts > %d" % self.ts)
+        tdSql.error("select twa(col5) from test1 where ts > %d" % self.ts)
+
+        tdSql.error("select twa(col6) from test where ts > %d" % self.ts)
+        tdSql.error("select twa(col6) from test1 where ts > %d" % self.ts)
+
+        tdSql.error("select twa(col1) from test where ts < %d" % (self.ts + self.rowNum))
+        tdSql.error("select twa(col1) from test1 where ts < %d" % (self.ts + self.rowNum))
+
+        tdSql.error("select twa(col2) from test where ts < %d" % (self.ts + self.rowNum))
+        tdSql.error("select twa(col2) from test1 where ts < %d" % (self.ts + self.rowNum))
+
+        tdSql.error("select twa(col3) from test where ts < %d" % (self.ts + self.rowNum))
+        tdSql.error("select twa(col3) from test1 where ts < %d" % (self.ts + self.rowNum))
+
+        tdSql.error("select twa(col4) from test where ts < %d" % (self.ts + self.rowNum))
+        tdSql.error("select twa(col4) from test1 where ts < %d" % (self.ts + self.rowNum))
+
+        tdSql.error("select twa(col5) from test where ts < %d" % (self.ts + self.rowNum))
+        tdSql.error("select twa(col5) from test1 where ts < %d" % (self.ts + self.rowNum))
+
+        tdSql.error("select twa(col6) from test where ts < %d" % (self.ts + self.rowNum))
+        tdSql.error("select twa(col6) from test1 where ts < %d" % (self.ts + self.rowNum))
+        
+        tdSql.query("select twa(col1) from test where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+        tdSql.query("select twa(col1) from test1 where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+
+        tdSql.query("select twa(col2) from test where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+        tdSql.query("select twa(col2) from test1 where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+
+        tdSql.query("select twa(col3) from test where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+        tdSql.query("select twa(col3) from test1 where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+
+        tdSql.query("select twa(col4) from test where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum)) 
+        tdSql.query("select twa(col4) from test1 where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+
+        tdSql.query("select twa(col5) from test where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum)) 
+        tdSql.query("select twa(col5) from test1 where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+
+        tdSql.query("select twa(col6) from test where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))         
+        tdSql.query("select twa(col6) from test1 where ts > %d  and ts < %d" % (self.ts, self.ts + self.rowNum))
+
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
diff --git a/tests/pytest/query/filterOtherTypes.py b/tests/pytest/query/filterOtherTypes.py
index 1db5497604923cecd8111015dd0ba497b914b453..5033ffdb48237e6a758d67162af5757cce04252d 100644
--- a/tests/pytest/query/filterOtherTypes.py
+++ b/tests/pytest/query/filterOtherTypes.py
@@ -231,10 +231,12 @@ class TDTestCase:
         tdSql.error("select * from st where tagcol1 like '____'")
 
         # > for nchar type on tag
-        tdSql.error("select * from st where tagcol2 > 'table'")
+        tdSql.query("select * from st where tagcol2 > 'table1'")
+        tdSql.checkRows(5)
 
         # >= for nchar type on tag
-        tdSql.error("select * from st where tagcol2 >= 'table'")
+        tdSql.query("select * from st where tagcol2 >= 'table1'")
+        tdSql.checkRows(10)
 
         # = for nchar type on tag
         tdSql.query("select * from st where tagcol2 = 'table1'")
@@ -249,10 +251,12 @@ class TDTestCase:
         tdSql.checkRows(10)
 
         # > for nchar type on tag
-        tdSql.error("select * from st where tagcol2 < 'table'")
+        tdSql.query("select * from st where tagcol2 < 'table'")
+        tdSql.checkRows(0)
 
         # >= for nchar type on tag
-        tdSql.error("select * from st where tagcol2 <= 'table'")
+        tdSql.query("select * from st where tagcol2 <= 'table'")
+        tdSql.checkRows(0)
 
         # % for nchar type on tag case 1
         tdSql.query("select * from st where tagcol2 like '%'")
@@ -291,10 +295,12 @@ class TDTestCase:
         tdSql.checkRows(10)
 
         # > for binary type on tag
-        tdSql.error("select * from st where tagcol3 > '表'")
+        tdSql.query("select * from st where tagcol3 > '表'")
+        tdSql.checkRows(10)
 
         # >= for binary type on tag
-        tdSql.error("select * from st where tagcol3 >= '表'")
+        tdSql.query("select * from st where tagcol3 >= '表'")
+        tdSql.checkRows(10)
 
         # = for binary type on tag
         tdSql.query("select * from st where tagcol3 = '水表'")
@@ -309,10 +315,12 @@ class TDTestCase:
         tdSql.checkRows(5)
 
         # > for binary type on tag
-        tdSql.error("select * from st where tagcol3 < '水表'")
+        tdSql.query("select * from st where tagcol3 < '水表'")
+        tdSql.checkRows(0)
 
         # >= for binary type on tag
-        tdSql.error("select * from st where tagcol3 <= '水表'")
+        tdSql.query("select * from st where tagcol3 <= '水表'")
+        tdSql.checkRows(5)
 
         # % for binary type on tag case 1
         tdSql.query("select * from st where tagcol3 like '%'")
diff --git a/tests/pytest/regressiontest.sh b/tests/pytest/regressiontest.sh
index 24cd93f0fc58772e2d1741d9ee0119d9d5247357..61ec491f5de6ed946aafe3e0f549c233f6a250b7 100755
--- a/tests/pytest/regressiontest.sh
+++ b/tests/pytest/regressiontest.sh
@@ -141,6 +141,7 @@ python3 ./test.py -f query/filterCombo.py
 python3 ./test.py -f query/queryNormal.py
 python3 ./test.py -f query/select_last_crash.py
 python3 ./test.py -f query/queryNullValueTest.py
+python3 ./test.py -f query/queryInsertValue.py
 
 #stream
 python3 ./test.py -f stream/stream1.py
@@ -155,3 +156,23 @@ python3 ./test.py -f client/client.py
 # Misc
 python3 testCompress.py
 python3 testNoCompress.py
+
+
+# functions
+python3 ./test.py -f functions/function_avg.py
+python3 ./test.py -f functions/function_bottom.py
+python3 ./test.py -f functions/function_count.py
+python3 ./test.py -f functions/function_diff.py
+python3 ./test.py -f functions/function_first.py
+python3 ./test.py -f functions/function_last.py
+python3 ./test.py -f functions/function_last_row.py
+python3 ./test.py -f functions/function_leastsquares.py
+python3 ./test.py -f functions/function_max.py
+python3 ./test.py -f functions/function_min.py
+python3 ./test.py -f functions/function_operations.py
+python3 ./test.py -f functions/function_percentile.py
+python3 ./test.py -f functions/function_spread.py
+python3 ./test.py -f functions/function_stddev.py
+python3 ./test.py -f functions/function_sum.py
+python3 ./test.py -f functions/function_top.py
+python3 ./test.py -f functions/function_twa.py
diff --git a/tests/pytest/util/sql.py b/tests/pytest/util/sql.py
index ec39ab61b9be2a52031dfcbb786cd6bc88fef555..1e1d02959f58e716a534a164aa72e3d18176d7c0 100644
--- a/tests/pytest/util/sql.py
+++ b/tests/pytest/util/sql.py
@@ -122,11 +122,16 @@ class TDSql:
         return self.cursor.istype(col, dataType)
 
     def checkData(self, row, col, data):
-        self.checkRowCol(row, col)
-        if self.queryResult[row][col] != data:
-            caller = inspect.getframeinfo(inspect.stack()[1][0])
-            args = (caller.filename, caller.lineno, self.sql, row, col, self.queryResult[row][col], data)
-            tdLog.exit("%s(%d) failed: sql:%s row:%d col:%d data:%s != expect:%s" % args)
+        self.checkRowCol(row, col)                
+        if self.queryResult[row][col] != data:            
+            if isinstance(data, float) and abs(self.queryResult[row][col] - data) <= 0.000001:                
+                tdLog.info("sql:%s, row:%d col:%d data:%f == expect:%f" %
+                            (self.sql, row, col, self.queryResult[row][col], data)) 
+                return
+            else:
+                caller = inspect.getframeinfo(inspect.stack()[1][0])
+                args = (caller.filename, caller.lineno, self.sql, row, col, self.queryResult[row][col], data)
+                tdLog.exit("%s(%d) failed: sql:%s row:%d col:%d data:%s != expect:%s" % args)        
 
         if data is None:
             tdLog.info("sql:%s, row:%d col:%d data:%s == expect:%s" %
@@ -135,9 +140,12 @@ class TDSql:
             tdLog.info("sql:%s, row:%d col:%d data:%s == expect:%s" %
                        (self.sql, row, col, self.queryResult[row][col], data))
         elif isinstance(data, datetime.date):
+            tdLog.info("sql:%s, row:%d col:%d data:%s == expect:%s" %
+                       (self.sql, row, col, self.queryResult[row][col], data))        
+        elif isinstance(data, float):
             tdLog.info("sql:%s, row:%d col:%d data:%s == expect:%s" %
                        (self.sql, row, col, self.queryResult[row][col], data))
-        else:
+        else:            
             tdLog.info("sql:%s, row:%d col:%d data:%s == expect:%d" %
                        (self.sql, row, col, self.queryResult[row][col], data))
 
diff --git a/tests/script/fullGeneralSuite.sim b/tests/script/fullGeneralSuite.sim
index 2f45ab077c095a89d04b780052f5c36ac67983ee..15cc2954e87c7c6f2e23472e8e22d347844bc6cf 100644
--- a/tests/script/fullGeneralSuite.sim
+++ b/tests/script/fullGeneralSuite.sim
@@ -135,7 +135,6 @@ run general/parser/set_tag_vals.sim
 #unsupport run general/parser/repeatAlter.sim
 #unsupport run general/parser/slimit_alter_tags.sim
 #unsupport run general/parser/stream_on_sys.sim
-run general/parser/stream.sim
 #unsupport run general/parser/repeatStream.sim
 run general/stable/disk.sim
 run general/stable/dnode3.sim
@@ -212,12 +211,9 @@ run general/vector/table_mix.sim
 run general/vector/table_query.sim
 run general/vector/table_time.sim
 run general/stream/restart_stream.sim
-run general/stream/stream_1.sim
-run general/stream/stream_2.sim
 run general/stream/stream_3.sim
 run general/stream/stream_restart.sim
 run general/stream/table_1.sim
-run general/stream/metrics_1.sim
 run general/stream/table_n.sim
 run general/stream/metrics_n.sim
 run general/stream/table_del.sim
diff --git a/tests/script/sh/exec-no-random-fail.sh b/tests/script/sh/exec-no-random-fail.sh
index 04a663bc5aed52208df7183013f6989945e5f760..2bd0a64923f73df010e40f427d40cb9e212480d7 100755
--- a/tests/script/sh/exec-no-random-fail.sh
+++ b/tests/script/sh/exec-no-random-fail.sh
@@ -88,7 +88,9 @@ if [ "$EXEC_OPTON" = "start" ]; then
   echo "ExcuteCmd:" $EXE_DIR/taosd -c $CFG_DIR
   
   if [ "$SHELL_OPTION" = "true" ]; then 
-    nohup valgrind --log-file=${LOG_DIR}/valgrind.log --tool=memcheck --leak-check=full --show-reachable=no  --track-origins=yes --show-leak-kinds=all  -v  --workaround-gcc296-bugs=yes   $EXE_DIR/taosd -c $CFG_DIR > /dev/null 2>&1 &   
+    TT=`date +%s`
+    mkdir ${LOG_DIR}/${TT}
+    nohup valgrind --log-file=${LOG_DIR}/${TT}/valgrind.log --tool=memcheck --leak-check=full --show-reachable=no  --track-origins=yes --show-leak-kinds=all  -v  --workaround-gcc296-bugs=yes   $EXE_DIR/taosd -c $CFG_DIR > /dev/null 2>&1 &   
   else
     nohup $EXE_DIR/taosd -c $CFG_DIR --random-file-fail-factor 0 > /dev/null 2>&1 & 
   fi
@@ -99,12 +101,12 @@ else
   PID=`ps -ef|grep taosd | grep $RCFG_DIR | grep -v grep | awk '{print $2}'`
   while [ -n "$PID" ]
   do
-    if [ "$SIGNAL" = "SIGINT" ]; then 
-      echo try to kill by signal SIGINT
-      kill -SIGINT $PID
-    else
+    if [ "$SIGNAL" = "SIGKILL" ]; then
       echo try to kill by signal SIGKILL
       kill -9 $PID
+    else
+      echo try to kill by signal SIGINT
+      kill -SIGINT $PID
     fi
     sleep 1
     PID=`ps -ef|grep taosd | grep $RCFG_DIR | grep -v grep | awk '{print $2}'`
diff --git a/tests/script/sh/exec-random-fail.sh b/tests/script/sh/exec-random-fail.sh
index a354021684884781e0157b011cf378dfb00dd924..3761498859591188799d1ad3814ed3b01372269d 100755
--- a/tests/script/sh/exec-random-fail.sh
+++ b/tests/script/sh/exec-random-fail.sh
@@ -88,9 +88,12 @@ if [ "$EXEC_OPTON" = "start" ]; then
   echo "ExcuteCmd:" $EXE_DIR/taosd -c $CFG_DIR
   
   if [ "$SHELL_OPTION" = "true" ]; then 
-    nohup valgrind --log-file=${LOG_DIR}/valgrind.log --tool=memcheck --leak-check=full --show-reachable=no  --track-origins=yes --show-leak-kinds=all  -v  --workaround-gcc296-bugs=yes   $EXE_DIR/taosd -c $CFG_DIR > /dev/null 2>&1 &   
+    TT=`date +%s`
+    mkdir ${LOG_DIR}/${TT}
+    nohup valgrind --log-file=${LOG_DIR}/${TT}/valgrind.log --tool=memcheck --leak-check=full --show-reachable=no  --track-origins=yes --show-leak-kinds=all  -v  --workaround-gcc296-bugs=yes   $EXE_DIR/taosd -c $CFG_DIR > /dev/null 2>&1 &   
   else
-    nohup $EXE_DIR/taosd -c $CFG_DIR --alloc-random-fail --random-file-fail-factor 5 > /dev/null 2>&1 & 
+    nohup $EXE_DIR/taosd -c $CFG_DIR  --alloc-random-fail \
+      --random-file-fail-factor 5 > /dev/null 2>&1 & 
   fi
   
 else
@@ -99,12 +102,12 @@ else
   PID=`ps -ef|grep taosd | grep $RCFG_DIR | grep -v grep | awk '{print $2}'`
   while [ -n "$PID" ]
   do
-    if [ "$SIGNAL" = "SIGINT" ]; then 
-      echo try to kill by signal SIGINT
-      kill -SIGINT $PID
-    else
+    if [ "$SIGNAL" = "SIGKILL" ]; then
       echo try to kill by signal SIGKILL
       kill -9 $PID
+    else
+      echo try to kill by signal SIGINT
+      kill -SIGINT $PID
     fi
     sleep 1
     PID=`ps -ef|grep taosd | grep $RCFG_DIR | grep -v grep | awk '{print $2}'`
diff --git a/tests/script/sh/exec.sh b/tests/script/sh/exec.sh
index 2f294075a1695298cb52b53bc52e11d9dce9fe07..1c84a6b10ed3f958e096d32eda727441ff2591da 100755
--- a/tests/script/sh/exec.sh
+++ b/tests/script/sh/exec.sh
@@ -101,12 +101,12 @@ else
   PID=`ps -ef|grep taosd | grep $RCFG_DIR | grep -v grep | awk '{print $2}'`
   while [ -n "$PID" ]
   do
-    if [ "$SIGNAL" = "SIGINT" ]; then 
-      echo try to kill by signal SIGINT
-      kill -SIGINT $PID
-    else
+    if [ "$SIGNAL" = "SIGKILL" ]; then
       echo try to kill by signal SIGKILL
       kill -9 $PID
+    else
+      echo try to kill by signal SIGINT
+      kill -SIGINT $PID
     fi
     sleep 1
     PID=`ps -ef|grep taosd | grep $RCFG_DIR | grep -v grep | awk '{print $2}'`