Merge remote-tracking branch 'origin/3.0_query_integrate' into feature/scheduler

include/common/taosdef.h

@@ -30,12 +30,13 @@ typedef int64_t tb_uid_t;
 #define IS_TSWINDOW_SPECIFIED(win) (((win).skey != INT64_MIN) || ((win).ekey != INT64_MAX))
 
 typedef enum {
-  TSDB_SUPER_TABLE = 1,   // super table
-  TSDB_CHILD_TABLE = 2,   // table created from super table
-  TSDB_NORMAL_TABLE = 3,  // ordinary table
-  TSDB_STREAM_TABLE = 4,  // table created from stream computing
-  TSDB_TEMP_TABLE = 5,    // temp table created by nest query
-  TSDB_TABLE_MAX = 6
+  TSDB_SUPER_TABLE  = 1,    // super table
+  TSDB_CHILD_TABLE  = 2,    // table created from super table
+  TSDB_NORMAL_TABLE = 3,    // ordinary table
+  TSDB_STREAM_TABLE = 4,    // table created from stream computing
+  TSDB_TEMP_TABLE   = 5,    // temp table created by nest query
+  TSDB_SYSTEM_TABLE = 6,
+  TSDB_TABLE_MAX    = 7
 } ETableType;
 
 typedef enum {

include/libs/function/function.h

@@ -163,7 +163,7 @@ typedef struct SInputColumnInfoData {
 typedef struct SqlFunctionCtx {
   SInputColumnInfoData input;
   SResultDataInfo      resDataInfo;
-  uint32_t             order;  // asc|desc
+  uint32_t             order;  // data block scanner order: asc|desc
   ////////////////////////////////////////////////////////////////
   int32_t          startRow;   // start row index
   int32_t          size;       // handled processed row number

include/libs/nodes/plannodes.h

@@ -36,7 +36,7 @@ typedef struct SLogicNode {
 typedef enum EScanType {
   SCAN_TYPE_TAG,
   SCAN_TYPE_TABLE,
-  SCAN_TYPE_STABLE,
+  SCAN_TYPE_SYSTEM_TABLE,
   SCAN_TYPE_STREAM
 } EScanType;
 
@@ -147,9 +147,13 @@ typedef struct SScanPhysiNode {
   SName tableName;
 } SScanPhysiNode;
 
-typedef SScanPhysiNode SSystemTableScanPhysiNode;
 typedef SScanPhysiNode STagScanPhysiNode;
 
+typedef struct SSystemTableScanPhysiNode {
+  SScanPhysiNode scan;
+  SEpSet mgmtEpSet;
+} SSystemTableScanPhysiNode;
+
 typedef struct STableScanPhysiNode {
   SScanPhysiNode scan;
   uint8_t scanFlag;         // denotes reversed scan of data or not

include/libs/planner/planner.h

@@ -25,6 +25,7 @@ extern "C" {
 typedef struct SPlanContext {
   uint64_t queryId;
   int32_t acctId;
+  SEpSet mgmtEpSet;
   SNode* pAstRoot;
 } SPlanContext;
 

include/util/tdef.h

@@ -99,7 +99,7 @@ extern const int32_t TYPE_BYTES[15];
 #define TSDB_INS_TABLE_MNODES                 "mnodes"
 #define TSDB_INS_TABLE_MODULES                "modules"
 #define TSDB_INS_TABLE_QNODES                 "qnodes"
-#define TSDB_INS_TABLE_USER_DATABASE          "user_database"
+#define TSDB_INS_TABLE_USER_DATABASES         "user_databases"
 #define TSDB_INS_TABLE_USER_FUNCTIONS         "user_functions"
 #define TSDB_INS_TABLE_USER_INDEXES           "user_indexes"
 #define TSDB_INS_TABLE_USER_STABLES           "user_stables"

source/client/src/clientImpl.c

@@ -194,7 +194,12 @@ int32_t execDdlQuery(SRequestObj* pRequest, SQuery* pQuery) {
 
 int32_t getPlan(SRequestObj* pRequest, SQuery* pQuery, SQueryPlan** pPlan, SArray* pNodeList) {
   pRequest->type = pQuery->msgType;
-  SPlanContext cxt = { .queryId = pRequest->requestId, .pAstRoot = pQuery->pRoot, .acctId = pRequest->pTscObj->acctId };
+  SPlanContext cxt = {
+    .queryId = pRequest->requestId,
+    .acctId = pRequest->pTscObj->acctId,
+    .mgmtEpSet = getEpSet_s(&pRequest->pTscObj->pAppInfo->mgmtEp),
+    .pAstRoot = pQuery->pRoot
+  };
   int32_t  code = qCreateQueryPlan(&cxt, pPlan, pNodeList);
   if (code != 0) {
     return code;

source/common/src/tmsg.c

@@ -1732,6 +1732,7 @@ int32_t tSerializeSRetrieveTableReq(void *buf, int32_t bufLen, SRetrieveTableReq
 
   if (tStartEncode(&encoder) < 0) return -1;
   if (tEncodeI64(&encoder, pReq->showId) < 0) return -1;
+  if (tEncodeI32(&encoder, pReq->type) < 0) return -1;
   if (tEncodeI8(&encoder, pReq->free) < 0) return -1;
   tEndEncode(&encoder);
 
@@ -1746,6 +1747,7 @@ int32_t tDeserializeSRetrieveTableReq(void *buf, int32_t bufLen, SRetrieveTableR
 
   if (tStartDecode(&decoder) < 0) return -1;
   if (tDecodeI64(&decoder, &pReq->showId) < 0) return -1;
+  if (tDecodeI32(&decoder, &pReq->type) < 0) return -1;
   if (tDecodeI8(&decoder, &pReq->free) < 0) return -1;
 
   tEndDecode(&decoder);

source/dnode/mgmt/impl/src/dndTransport.c

@@ -102,6 +102,7 @@ static void dndInitMsgFp(STransMgmt *pMgmt) {
   pMgmt->msgFp[TMSG_INDEX(TDMT_MND_HEARTBEAT)] = dndProcessMnodeWriteMsg;
   pMgmt->msgFp[TMSG_INDEX(TDMT_MND_SHOW)] = dndProcessMnodeReadMsg;
   pMgmt->msgFp[TMSG_INDEX(TDMT_MND_SHOW_RETRIEVE)] = dndProcessMnodeReadMsg;
+  pMgmt->msgFp[TMSG_INDEX(TDMT_MND_SYSTABLE_RETRIEVE)] = dndProcessMnodeReadMsg;
   pMgmt->msgFp[TMSG_INDEX(TDMT_MND_STATUS)] = dndProcessMnodeReadMsg;
   pMgmt->msgFp[TMSG_INDEX(TDMT_MND_STATUS_RSP)] = dndProcessMgmtMsg;
   pMgmt->msgFp[TMSG_INDEX(TDMT_MND_KILL_TRANS)] = dndProcessMnodeWriteMsg;

source/dnode/mnode/impl/src/mndDb.c

@@ -1342,123 +1342,149 @@ char *mnGetDbStr(char *src) {
   return pos;
 }
 
-static int32_t mndRetrieveDbs(SMnodeMsg *pReq, SShowObj *pShow, char *data, int32_t rows) {
-  SMnode *pMnode = pReq->pMnode;
-  SSdb   *pSdb = pMnode->pSdb;
-  int32_t numOfRows = 0;
-  SDbObj *pDb = NULL;
-  char   *pWrite;
+static char* getDataPosition(char* pData, SShowObj* pShow, int32_t cols, int32_t rows, int32_t capacityOfRow) {
+  return pData + pShow->offset[cols] * capacityOfRow + pShow->bytes[cols] * rows;
+}
+
+static void dumpDbInfoToPayload(char* data, SDbObj* pDb, SShowObj* pShow, int32_t rows, int32_t rowCapacity, int64_t numOfTables) {
   int32_t cols = 0;
 
-  while (numOfRows < rows) {
-    pShow->pIter = sdbFetch(pSdb, SDB_DB, pShow->pIter, (void **)&pDb);
-    if (pShow->pIter == NULL) break;
+  char* pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  char *name = mnGetDbStr(pDb->name);
+  if (name != NULL) {
+    STR_WITH_MAXSIZE_TO_VARSTR(pWrite, name, pShow->bytes[cols]);
+  } else {
+    STR_TO_VARSTR(pWrite, "NULL");
+  }
+  cols++;
 
-    cols = 0;
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  *(int64_t *)pWrite = pDb->createdTime;
+  cols++;
 
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    char *name = mnGetDbStr(pDb->name);
-    if (name != NULL) {
-      STR_WITH_MAXSIZE_TO_VARSTR(pWrite, name, pShow->bytes[cols]);
-    } else {
-      STR_TO_VARSTR(pWrite, "NULL");
-    }
-    cols++;
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  *(int16_t *)pWrite = pDb->cfg.numOfVgroups;
+  cols++;
+
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  *(int64_t *)pWrite = numOfTables;
+  cols++;
 
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    *(int64_t *)pWrite = pDb->createdTime;
-    cols++;
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  *(int16_t *)pWrite = pDb->cfg.replications;
+  cols++;
 
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    *(int16_t *)pWrite = pDb->cfg.numOfVgroups;
-    cols++;
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  *(int16_t *)pWrite = pDb->cfg.quorum;
+  cols++;
 
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    *(int16_t *)pWrite = 0;  // todo
-    cols++;
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  *(int16_t *)pWrite = pDb->cfg.daysPerFile;
+  cols++;
 
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    *(int16_t *)pWrite = pDb->cfg.replications;
-    cols++;
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  char tmp[128] = {0};
+  if (pDb->cfg.daysToKeep0 > pDb->cfg.daysToKeep1 || pDb->cfg.daysToKeep0 > pDb->cfg.daysToKeep2) {
+    sprintf(tmp, "%d,%d,%d", pDb->cfg.daysToKeep1, pDb->cfg.daysToKeep2, pDb->cfg.daysToKeep0);
+  } else {
+    sprintf(tmp, "%d,%d,%d", pDb->cfg.daysToKeep0, pDb->cfg.daysToKeep1, pDb->cfg.daysToKeep2);
+  }
+  STR_WITH_SIZE_TO_VARSTR(pWrite, tmp, strlen(tmp));
+  cols++;
 
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    *(int16_t *)pWrite = pDb->cfg.quorum;
-    cols++;
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  *(int32_t *)pWrite = pDb->cfg.cacheBlockSize;
+  cols++;
 
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    *(int16_t *)pWrite = pDb->cfg.daysPerFile;
-    cols++;
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  *(int32_t *)pWrite = pDb->cfg.totalBlocks;
+  cols++;
 
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    char tmp[128] = {0};
-    if (pDb->cfg.daysToKeep0 > pDb->cfg.daysToKeep1 || pDb->cfg.daysToKeep0 > pDb->cfg.daysToKeep2) {
-      sprintf(tmp, "%d,%d,%d", pDb->cfg.daysToKeep1, pDb->cfg.daysToKeep2, pDb->cfg.daysToKeep0);
-    } else {
-      sprintf(tmp, "%d,%d,%d", pDb->cfg.daysToKeep0, pDb->cfg.daysToKeep1, pDb->cfg.daysToKeep2);
-    }
-    STR_WITH_SIZE_TO_VARSTR(pWrite, tmp, strlen(tmp));
-    cols++;
-
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    *(int32_t *)pWrite = pDb->cfg.cacheBlockSize;
-    cols++;
-
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    *(int32_t *)pWrite = pDb->cfg.totalBlocks;
-    cols++;
-
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    *(int32_t *)pWrite = pDb->cfg.minRows;
-    cols++;
-
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    *(int32_t *)pWrite = pDb->cfg.maxRows;
-    cols++;
-
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    *(int8_t *)pWrite = pDb->cfg.walLevel;
-    cols++;
-
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    *(int32_t *)pWrite = pDb->cfg.fsyncPeriod;
-    cols++;
-
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    *(int8_t *)pWrite = pDb->cfg.compression;
-    cols++;
-
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    *(int8_t *)pWrite = pDb->cfg.cacheLastRow;
-    cols++;
-
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    char *prec = NULL;
-    switch (pDb->cfg.precision) {
-      case TSDB_TIME_PRECISION_MILLI:
-        prec = TSDB_TIME_PRECISION_MILLI_STR;
-        break;
-      case TSDB_TIME_PRECISION_MICRO:
-        prec = TSDB_TIME_PRECISION_MICRO_STR;
-        break;
-      case TSDB_TIME_PRECISION_NANO:
-        prec = TSDB_TIME_PRECISION_NANO_STR;
-        break;
-      default:
-        prec = "none";
-        break;
-    }
-    STR_WITH_SIZE_TO_VARSTR(pWrite, prec, 2);
-    cols++;
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  *(int32_t *)pWrite = pDb->cfg.minRows;
+  cols++;
+
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  *(int32_t *)pWrite = pDb->cfg.maxRows;
+  cols++;
 
-    pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
-    *(int8_t *)pWrite = pDb->cfg.update;
-    cols++;
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  *(int8_t *)pWrite = pDb->cfg.walLevel;
+  cols++;
+
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  *(int32_t *)pWrite = pDb->cfg.fsyncPeriod;
+  cols++;
+
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  *(int8_t *)pWrite = pDb->cfg.compression;
+  cols++;
+
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  *(int8_t *)pWrite = pDb->cfg.cacheLastRow;
+  cols++;
+
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  char *prec = NULL;
+  switch (pDb->cfg.precision) {
+    case TSDB_TIME_PRECISION_MILLI:
+      prec = TSDB_TIME_PRECISION_MILLI_STR;
+      break;
+    case TSDB_TIME_PRECISION_MICRO:
+      prec = TSDB_TIME_PRECISION_MICRO_STR;
+      break;
+    case TSDB_TIME_PRECISION_NANO:
+      prec = TSDB_TIME_PRECISION_NANO_STR;
+      break;
+    default:
+      prec = "none";
+      break;
+  }
+  STR_WITH_SIZE_TO_VARSTR(pWrite, prec, 2);
+  cols++;
+
+  pWrite = getDataPosition(data, pShow, cols, rows, rowCapacity);
+  *(int8_t *)pWrite = pDb->cfg.update;
+}
+
+static void setInformationSchemaDbCfg(SDbObj* pDbObj) {
+  ASSERT(pDbObj != NULL);
+  strncpy(pDbObj->name, TSDB_INFORMATION_SCHEMA_DB, tListLen(pDbObj->name));
+
+  pDbObj->createdTime      = 0;
+  pDbObj->cfg.numOfVgroups = 0;
+  pDbObj->cfg.quorum       = 1;
+  pDbObj->cfg.replications = 1;
+  pDbObj->cfg.update       = 1;
+  pDbObj->cfg.precision    = TSDB_TIME_PRECISION_MILLI;
+}
 
+static int32_t mndRetrieveDbs(SMnodeMsg *pReq, SShowObj *pShow, char *data, int32_t rowsCapacity) {
+  SMnode *pMnode = pReq->pMnode;
+  SSdb   *pSdb = pMnode->pSdb;
+  int32_t numOfRows = 0;
+  SDbObj *pDb = NULL;
+
+  while (numOfRows < rowsCapacity) {
+    pShow->pIter = sdbFetch(pSdb, SDB_DB, pShow->pIter, (void **)&pDb);
+    if (pShow->pIter == NULL) {
+      break;
+    }
+
+    dumpDbInfoToPayload(data, pDb, pShow, numOfRows, rowsCapacity, 0);
     numOfRows++;
     sdbRelease(pSdb, pDb);
   }
 
-  mndVacuumResult(data, pShow->numOfColumns, numOfRows, rows, pShow);
+  // Append the information_schema database into the result.
+  if (numOfRows < rowsCapacity) {
+    SDbObj dummyISDb = {0};
+    setInformationSchemaDbCfg(&dummyISDb);
+    dumpDbInfoToPayload(data, &dummyISDb, pShow, numOfRows, rowsCapacity, 14);
+    numOfRows += 1;
+  }
+
+  mndVacuumResult(data, pShow->numOfColumns, numOfRows, rowsCapacity, pShow);
   pShow->numOfReads += numOfRows;
 
   return numOfRows;

source/dnode/mnode/impl/src/mndInfoSchema.c

@@ -39,24 +39,24 @@ static const SInfosTableSchema qnodesSchema[] = {{.name = "id",             .byt
                                                  {.name = "end_point",      .bytes = 134, .type = TSDB_DATA_TYPE_BINARY},
                                                  {.name = "create_time",    .bytes = 8,   .type = TSDB_DATA_TYPE_TIMESTAMP},
                                                 };
-static const SInfosTableSchema userDBSchema[] = {{.name = "name",             .bytes = 32,   .type = TSDB_DATA_TYPE_BINARY},
+static const SInfosTableSchema userDBSchema[] = {{.name = "name",             .bytes = (TSDB_DB_NAME_LEN - 1) + VARSTR_HEADER_SIZE,   .type = TSDB_DATA_TYPE_BINARY},
                                                  {.name = "created_time",     .bytes = 8,    .type = TSDB_DATA_TYPE_TIMESTAMP},
-                                                 {.name = "ntables",          .bytes = 4,    .type = TSDB_DATA_TYPE_INT},
-                                                 {.name = "vgroups",          .bytes = 4,    .type = TSDB_DATA_TYPE_INT},
-                                                 {.name = "replica",          .bytes = 4,    .type = TSDB_DATA_TYPE_INT},
-                                                 {.name = "quorum",           .bytes = 4,    .type = TSDB_DATA_TYPE_INT},
-                                                 {.name = "days",             .bytes = 4,    .type = TSDB_DATA_TYPE_INT},
-                                                 {.name = "keep",             .bytes = 4,    .type = TSDB_DATA_TYPE_INT},
+                                                 {.name = "vgroups",          .bytes = 2,    .type = TSDB_DATA_TYPE_SMALLINT},
+                                                 {.name = "ntables",          .bytes = 8,    .type = TSDB_DATA_TYPE_BIGINT},
+                                                 {.name = "replica",          .bytes = 2,    .type = TSDB_DATA_TYPE_SMALLINT},
+                                                 {.name = "quorum",           .bytes = 2,    .type = TSDB_DATA_TYPE_SMALLINT},
+                                                 {.name = "days",             .bytes = 2,    .type = TSDB_DATA_TYPE_SMALLINT},
+                                                 {.name = "keep",             .bytes = 24 + VARSTR_HEADER_SIZE,    .type = TSDB_DATA_TYPE_BINARY},
                                                  {.name = "cache",            .bytes = 4,    .type = TSDB_DATA_TYPE_INT},
                                                  {.name = "blocks",           .bytes = 4,    .type = TSDB_DATA_TYPE_INT},
                                                  {.name = "minrows",          .bytes = 4,    .type = TSDB_DATA_TYPE_INT},
                                                  {.name = "maxrows",          .bytes = 4,    .type = TSDB_DATA_TYPE_INT},
-                                                 {.name = "wallevel",         .bytes = 4,    .type = TSDB_DATA_TYPE_INT},
+                                                 {.name = "wallevel",         .bytes = 1,    .type = TSDB_DATA_TYPE_TINYINT},
                                                  {.name = "fsync",            .bytes = 4,    .type = TSDB_DATA_TYPE_INT},
-                                                 {.name = "comp",             .bytes = 4,    .type = TSDB_DATA_TYPE_INT},
-                                                 {.name = "cachelast",        .bytes = 4,    .type = TSDB_DATA_TYPE_INT},
-                                                 {.name = "precision",        .bytes = 2,    .type = TSDB_DATA_TYPE_BINARY},
-                                                 {.name = "status",           .bytes = 10,   .type = TSDB_DATA_TYPE_BINARY},
+                                                 {.name = "comp",             .bytes = 1,    .type = TSDB_DATA_TYPE_TINYINT},
+                                                 {.name = "cachelast",        .bytes = 1,    .type = TSDB_DATA_TYPE_TINYINT},
+                                                 {.name = "precision",        .bytes = 3 + VARSTR_HEADER_SIZE,    .type = TSDB_DATA_TYPE_BINARY},
+                                                 {.name = "update",           .bytes = 1,   .type = TSDB_DATA_TYPE_TINYINT},
                                                 };
 static const SInfosTableSchema userFuncSchema[] = {{.name = "name",           .bytes = 32,   .type = TSDB_DATA_TYPE_BINARY},
                                                    {.name = "created_time",   .bytes = 8,    .type = TSDB_DATA_TYPE_TIMESTAMP},
@@ -128,7 +128,7 @@ static const SInfosTableMeta infosMeta[] = {{TSDB_INS_TABLE_DNODES, dnodesSchema
                                             {TSDB_INS_TABLE_MNODES, mnodesSchema, tListLen(mnodesSchema)},
                                             {TSDB_INS_TABLE_MODULES, modulesSchema, tListLen(modulesSchema)},
                                             {TSDB_INS_TABLE_QNODES, qnodesSchema, tListLen(qnodesSchema)},
-                                            {TSDB_INS_TABLE_USER_DATABASE, userDBSchema, tListLen(userDBSchema)},
+                                            {TSDB_INS_TABLE_USER_DATABASES, userDBSchema, tListLen(userDBSchema)},
                                             {TSDB_INS_TABLE_USER_FUNCTIONS, userFuncSchema, tListLen(userFuncSchema)},
                                             {TSDB_INS_TABLE_USER_INDEXES, userIdxSchema, tListLen(userIdxSchema)},
                                             {TSDB_INS_TABLE_USER_STABLES, userStbsSchema, tListLen(userStbsSchema)},
@@ -165,7 +165,7 @@ int32_t mndInsInitMeta(SHashObj *hash) {
   STableMetaRsp meta = {0};
 
   strcpy(meta.dbFName, TSDB_INFORMATION_SCHEMA_DB);
-  meta.tableType = TSDB_NORMAL_TABLE;
+  meta.tableType = TSDB_SYSTEM_TABLE;
   meta.sversion = 1;
   meta.tversion = 1;
 

source/dnode/mnode/impl/src/mndShow.c

@@ -284,6 +284,20 @@ static int32_t mndProcessRetrieveSysTableReq(SMnodeMsg *pReq) {
     strncpy(req.db, retrieveReq.db, tListLen(req.db));
 
     pShow = mndCreateShowObj(pMnode, &req);
+    STableMetaRsp *meta = (STableMetaRsp *)taosHashGet(pMnode->infosMeta, TSDB_INS_TABLE_USER_DATABASES, strlen(TSDB_INS_TABLE_USER_DATABASES));
+    pShow->numOfRows = 100;
+
+    int32_t offset = 0;
+    for(int32_t i = 0; i < meta->numOfColumns; ++i) {
+      pShow->numOfColumns = meta->numOfColumns;
+      pShow->offset[i] = offset;
+
+      int32_t bytes = meta->pSchemas[i].bytes;
+      pShow->rowSize += bytes;
+      pShow->bytes[i] = bytes;
+      offset += bytes;
+    }
+
     if (pShow == NULL) {
       terrno = TSDB_CODE_OUT_OF_MEMORY;
       mError("failed to process show-meta req since %s", terrstr());
@@ -330,7 +344,7 @@ static int32_t mndProcessRetrieveSysTableReq(SMnodeMsg *pReq) {
   size = pShow->rowSize * rowsToRead;
 
   size += SHOW_STEP_SIZE;
-  SRetrieveTableRsp *pRsp = rpcMallocCont(size);
+  SRetrieveMetaTableRsp *pRsp = rpcMallocCont(size);
   if (pRsp == NULL) {
     mndReleaseShowObj((SShowObj*) pShow, false);
     terrno = TSDB_CODE_OUT_OF_MEMORY;
@@ -338,6 +352,8 @@ static int32_t mndProcessRetrieveSysTableReq(SMnodeMsg *pReq) {
     return -1;
   }
 
+  pRsp->handle = htobe64(pShow->id);
+
   // if free flag is set, client wants to clean the resources
   if ((retrieveReq.free & TSDB_QUERY_TYPE_FREE_RESOURCE) != TSDB_QUERY_TYPE_FREE_RESOURCE) {
     rowsRead = (*retrieveFp)(pReq, (SShowObj*) pShow, pRsp->data, rowsToRead);

source/libs/executor/inc/executorimpl.h

@@ -365,28 +365,6 @@ typedef struct SQInfo {
   STaskCostInfo   summary;
 } SQInfo;
 
-typedef struct STaskParam {
-  char*      sql;
-  char*      tagCond;
-  char*      colCond;
-  char*      tbnameCond;
-  char*      prevResult;
-  SArray*    pTableIdList;
-  SExprBasicInfo** pExpr;
-  SExprBasicInfo** pSecExpr;
-  SExprInfo* pExprs;
-  SExprInfo* pSecExprs;
-
-  SFilterInfo* pFilters;
-
-  SColIndex*       pGroupColIndex;
-  SColumnInfo*     pTagColumnInfo;
-  SGroupbyExpr*    pGroupbyExpr;
-  int32_t          tableScanOperator;
-  SArray*          pOperator;
-  struct SUdfInfo* pUdfInfo;
-} STaskParam;
-
 enum {
   EX_SOURCE_DATA_NOT_READY = 0x1,
   EX_SOURCE_DATA_READY     = 0x2,
@@ -401,6 +379,12 @@ typedef struct SSourceDataInfo {
   int32_t            status;
 } SSourceDataInfo;
 
+typedef struct SLoadRemoteDataInfo {
+  uint64_t           totalSize;     // total load bytes from remote
+  uint64_t           totalRows;     // total number of rows
+  uint64_t           totalElapsed;  // total elapsed time
+} SLoadRemoteDataInfo;
+
 typedef struct SExchangeInfo {
   SArray*            pSources;
   SArray*            pSourceDataInfo;
@@ -409,9 +393,7 @@ typedef struct SExchangeInfo {
   SSDataBlock*       pResult;
   bool               seqLoadData;   // sequential load data or not, false by default
   int32_t            current;
-  uint64_t           totalSize;     // total load bytes from remote
-  uint64_t           totalRows;     // total number of rows
-  uint64_t           totalElapsed;  // total elapsed time
+  SLoadRemoteDataInfo loadInfo;
 } SExchangeInfo;
 
 typedef struct STableScanInfo {
@@ -456,19 +438,17 @@ typedef struct SSysTableScanInfo {
     void* readHandle;
   };
 
-  void              *pCur; // cursor
-  SRetrieveTableReq* pReq;
-  SEpSet             epSet;
-  int32_t            type;  // show type
-  tsem_t             ready;
-  SSchema*           pSchema;
-  SSDataBlock*       pRes;
-
-  int32_t            capacity;
-  int64_t            numOfBlocks;  // extract basic running information.
-  int64_t            totalRows;
-  int64_t            elapsedTime;
-  int64_t            totalBytes;
+  SRetrieveMetaTableRsp *pRsp;
+  void               *pCur; // cursor
+  SRetrieveTableReq   req;
+  SEpSet              epSet;
+  int32_t             type;  // show type
+  tsem_t              ready;
+  SSchema*            pSchema;
+  SSDataBlock*        pRes;
+  int32_t             capacity;
+  int64_t             numOfBlocks;  // extract basic running information.
+  SLoadRemoteDataInfo loadInfo;
 } SSysTableScanInfo;
 
 typedef struct SOptrBasicInfo {
@@ -649,10 +629,8 @@ SOperatorInfo* createTableSeqScanOperatorInfo(void* pTsdbReadHandle, STaskRuntim
 SOperatorInfo* createAggregateOperatorInfo(SOperatorInfo* downstream, SArray* pExprInfo, SSDataBlock* pResultBlock, SExecTaskInfo* pTaskInfo, const STableGroupInfo* pTableGroupInfo);
 SOperatorInfo* createMultiTableAggOperatorInfo(SOperatorInfo* downstream, SArray* pExprInfo, SSDataBlock* pResultBlock, SExecTaskInfo* pTaskInfo, const STableGroupInfo* pTableGroupInfo);
 SOperatorInfo* createProjectOperatorInfo(SOperatorInfo* downstream, SArray* pExprInfo, SExecTaskInfo* pTaskInfo);
-SOperatorInfo* createOrderOperatorInfo(SOperatorInfo* downstream, SArray* pExprInfo, SArray* pOrderVal, SExecTaskInfo* pTaskInfo);
-SOperatorInfo* createSortedMergeOperatorInfo(SOperatorInfo** downstream, int32_t numOfDownstream, SArray* pExprInfo, SArray* pOrderVal, SArray* pGroupInfo, SExecTaskInfo* pTaskInfo);
-SOperatorInfo* createSysTableScanOperatorInfo(void* pSysTableReadHandle, const SArray* pExprInfo, const SSchema* pSchema,
-                                              int32_t tableType, SEpSet epset, SExecTaskInfo* pTaskInfo);
+SOperatorInfo* createSysTableScanOperatorInfo(void* pSysTableReadHandle, SSDataBlock* pResBlock, int32_t tableType, SEpSet epset,
+                                              SExecTaskInfo* pTaskInfo);
 
 SOperatorInfo* createLimitOperatorInfo(STaskRuntimeEnv* pRuntimeEnv, SOperatorInfo* downstream);
 SOperatorInfo* createIntervalOperatorInfo(SOperatorInfo* downstream, SArray* pExprInfo, SInterval* pInterval, SExecTaskInfo* pTaskInfo);
@@ -688,8 +666,10 @@ SOperatorInfo* createSLimitOperatorInfo(STaskRuntimeEnv* pRuntimeEnv, SOperatorI
 
 SOperatorInfo* createJoinOperatorInfo(SOperatorInfo** pdownstream, int32_t numOfDownstream, SSchema* pSchema,
                                       int32_t numOfOutput);
+SOperatorInfo* createOrderOperatorInfo(SOperatorInfo* downstream, SArray* pExprInfo, SArray* pOrderVal, SExecTaskInfo* pTaskInfo);
+SOperatorInfo* createSortedMergeOperatorInfo(SOperatorInfo** downstream, int32_t numOfDownstream, SArray* pExprInfo, SArray* pOrderVal, SArray* pGroupInfo, SExecTaskInfo* pTaskInfo);
 
-// int32_t doCreateFilterInfo(SColumnInfo* pCols, int32_t numOfCols, int32_t numOfFilterCols, SSingleColumnFilterInfo** pFilterInfo, uint64_t qId);
+// SSDataBlock* doSLimit(void* param, bool* newgroup);
 void doSetFilterColumnInfo(SSingleColumnFilterInfo* pFilterInfo, int32_t numOfFilterCols, SSDataBlock* pBlock);
 bool doFilterDataBlock(SSingleColumnFilterInfo* pFilterInfo, int32_t numOfFilterCols, int32_t numOfRows, int8_t* p);
 void doCompactSDataBlock(SSDataBlock* pBlock, int32_t numOfRows, int8_t* p);
@@ -706,9 +686,6 @@ void copyTsColoum(SSDataBlock* pRes, SqlFunctionCtx* pCtx, int32_t numOfOutput);
 
 int32_t createQueryFilter(char* data, uint16_t len, SFilterInfo** pFilters);
 
-int32_t initQInfo(STsBufInfo* pTsBufInfo, void* tsdb, void* sourceOptr, SQInfo* pQInfo, STaskParam* param, char* start,
-                  int32_t prevResultLen, void* merger);
-
 int32_t createFilterInfo(STaskAttr* pQueryAttr, uint64_t qId);
 void    freeColumnFilterInfo(SColumnFilterInfo* pFilter, int32_t numOfFilters);
 
@@ -720,11 +697,7 @@ int32_t buildArithmeticExprFromMsg(SExprInfo* pArithExprInfo, void* pQueryMsg);
 bool    isTaskKilled(SExecTaskInfo* pTaskInfo);
 int32_t checkForQueryBuf(size_t numOfTables);
 bool    checkNeedToCompressQueryCol(SQInfo* pQInfo);
-void    setQueryStatus(STaskRuntimeEnv* pRuntimeEnv, int8_t status);
 
-int32_t doDumpQueryResult(SQInfo* pQInfo, char* data, int8_t compressed, int32_t* compLen);
-
-size_t getResultSize(SQInfo* pQInfo, int64_t* numOfRows);
 void   setTaskKilled(SExecTaskInfo* pTaskInfo);
 
 void publishOperatorProfEvent(SOperatorInfo* operatorInfo, EQueryProfEventType eventType);
@@ -734,8 +707,6 @@ void calculateOperatorProfResults(SQInfo* pQInfo);
 void queryCostStatis(SExecTaskInfo* pTaskInfo);
 
 void doDestroyTask(SExecTaskInfo* pTaskInfo);
-void freeQueryAttr(STaskAttr* pQuery);
-
 int32_t getMaximumIdleDurationSec();
 
 void    doInvokeUdf(struct SUdfInfo* pUdfInfo, SqlFunctionCtx* pCtx, int32_t idx, int32_t type);

source/libs/executor/src/executorimpl.c

@@ -4975,35 +4975,36 @@ static int32_t doSendFetchDataRequest(SExchangeInfo *pExchangeInfo, SExecTaskInf
   return TSDB_CODE_SUCCESS;
 }
 
-static int32_t setSDataBlockFromFetchRsp(SSDataBlock* pRes, SExchangeInfo *pExchangeInfo, SSourceDataInfo* pDataInfo, int32_t numOfOutput, int64_t startTs) {
-  char* pData = pDataInfo->pRsp->data;
-  SRetrieveTableRsp* pRsp = pDataInfo->pRsp;
+static int32_t setSDataBlockFromFetchRsp(SSDataBlock* pRes, SLoadRemoteDataInfo* pLoadInfo, int32_t numOfRows, char* pData, int32_t compLen,
+    int32_t numOfOutput, int64_t startTs, uint64_t* total) {
+//  char* pData = pRsp->data;
 
   for (int32_t i = 0; i < numOfOutput; ++i) {
     SColumnInfoData* pColInfoData = taosArrayGet(pRes->pDataBlock, i);
 
-    char* tmp = realloc(pColInfoData->pData, pColInfoData->info.bytes * pRsp->numOfRows);
+    char* tmp = realloc(pColInfoData->pData, pColInfoData->info.bytes * numOfRows);
     if (tmp == NULL) {
       return TSDB_CODE_QRY_OUT_OF_MEMORY;
     }
 
-    size_t len = pRsp->numOfRows * pColInfoData->info.bytes;
+    size_t len = numOfRows * pColInfoData->info.bytes;
     memcpy(tmp, pData, len);
-
     pColInfoData->pData = tmp;
     pData += len;
   }
 
-  pRes->info.rows = pRsp->numOfRows;
+  pRes->info.rows = numOfRows;
 
   int64_t el = taosGetTimestampUs() - startTs;
 
-  pExchangeInfo->totalRows += pRsp->numOfRows;
-  pExchangeInfo->totalSize += pRsp->compLen;
-  pDataInfo->totalRows += pRsp->numOfRows;
+  pLoadInfo->totalRows += numOfRows;
+  pLoadInfo->totalSize += compLen;
 
-  pExchangeInfo->totalElapsed += el;
+  if (total != NULL) {
+    *total += numOfRows;
+  }
 
+  pLoadInfo->totalElapsed += el;
   return TSDB_CODE_SUCCESS;
 }
 
@@ -5012,11 +5013,12 @@ static void* setAllSourcesCompleted(SOperatorInfo *pOperator, int64_t startTs) {
   SExecTaskInfo* pTaskInfo = pOperator->pTaskInfo;
 
   int64_t el = taosGetTimestampUs() - startTs;
-  pExchangeInfo->totalElapsed += el;
+  SLoadRemoteDataInfo* pLoadInfo = &pExchangeInfo->loadInfo;
+  pLoadInfo->totalElapsed += el;
 
   size_t totalSources = taosArrayGetSize(pExchangeInfo->pSources);
   qDebug("%s all %"PRIzu" sources are exhausted, total rows: %"PRIu64" bytes:%"PRIu64", elapsed:%.2f ms", GET_TASKID(pTaskInfo), totalSources,
-         pExchangeInfo->totalRows, pExchangeInfo->totalSize, pExchangeInfo->totalElapsed/1000.0);
+         pLoadInfo->totalRows, pLoadInfo->totalSize, pLoadInfo->totalElapsed/1000.0);
 
   doSetOperatorCompleted(pOperator);
   return NULL;
@@ -5045,17 +5047,19 @@ static SSDataBlock* concurrentlyLoadRemoteDataImpl(SOperatorInfo *pOperator, SEx
       SDownstreamSourceNode* pSource = taosArrayGet(pExchangeInfo->pSources, i);
 
       SSDataBlock* pRes = pExchangeInfo->pResult;
-
+      SLoadRemoteDataInfo* pLoadInfo = &pExchangeInfo->loadInfo;
       if (pRsp->numOfRows == 0) {
         qDebug("%s vgId:%d, taskID:0x%" PRIx64 " index:%d completed, rowsOfSource:%" PRIu64 ", totalRows:%" PRIu64 " try next",
                GET_TASKID(pTaskInfo), pSource->addr.nodeId, pSource->taskId, i + 1, pDataInfo->totalRows,
-               pExchangeInfo->totalRows);
-        pDataInfo->status = EX_SOURCE_DATA_EXHAUSTED;
+               pExchangeInfo->loadInfo.totalRows);
+        pDataInfo->status = DATA_EXHAUSTED;
         completed += 1;
         continue;
       }
 
-      code = setSDataBlockFromFetchRsp(pExchangeInfo->pResult, pExchangeInfo, pDataInfo, pOperator->numOfOutput, startTs);
+      SRetrieveTableRsp* pTableRsp = pDataInfo->pRsp;
+      code = setSDataBlockFromFetchRsp(pExchangeInfo->pResult, pLoadInfo, pTableRsp->numOfRows,
+                                       pTableRsp->data, pTableRsp->compLen, pOperator->numOfOutput, startTs, &pDataInfo->totalRows);
       if (code != 0) {
         goto _error;
       }
@@ -5064,13 +5068,13 @@ static SSDataBlock* concurrentlyLoadRemoteDataImpl(SOperatorInfo *pOperator, SEx
         qDebug("%s fetch msg rsp from vgId:%d, taskId:0x%" PRIx64 " numOfRows:%d, rowsOfSource:%" PRIu64
                ", totalRows:%" PRIu64 ", totalBytes:%" PRIu64 " try next %d/%" PRIzu,
                GET_TASKID(pTaskInfo), pSource->addr.nodeId, pSource->taskId, pRes->info.rows,
-               pDataInfo->totalRows, pExchangeInfo->totalRows, pExchangeInfo->totalSize, i + 1,
+               pDataInfo->totalRows, pLoadInfo->totalRows, pLoadInfo->totalSize, i + 1,
                totalSources);
         pDataInfo->status = EX_SOURCE_DATA_EXHAUSTED;
       } else {
         qDebug("%s fetch msg rsp from vgId:%d, taskId:0x%" PRIx64 " numOfRows:%d, totalRows:%" PRIu64 ", totalBytes:%" PRIu64,
-               GET_TASKID(pTaskInfo), pSource->addr.nodeId, pSource->taskId, pRes->info.rows, pExchangeInfo->totalRows,
-               pExchangeInfo->totalSize);
+               GET_TASKID(pTaskInfo), pSource->addr.nodeId, pSource->taskId, pRes->info.rows, pLoadInfo->totalRows,
+               pLoadInfo->totalSize);
       }
 
       if (pDataInfo->status != EX_SOURCE_DATA_EXHAUSTED) {
@@ -5139,10 +5143,12 @@ static SSDataBlock* seqLoadRemoteData(SOperatorInfo *pOperator) {
     SDownstreamSourceNode* pSource = taosArrayGet(pExchangeInfo->pSources, pExchangeInfo->current);
 
     SRetrieveTableRsp* pRsp = pDataInfo->pRsp;
+    SLoadRemoteDataInfo* pLoadInfo = &pExchangeInfo->loadInfo;
+
     if (pRsp->numOfRows == 0) {
       qDebug("%s vgId:%d, taskID:0x%"PRIx64" %d of total completed, rowsOfSource:%"PRIu64", totalRows:%"PRIu64" try next",
              GET_TASKID(pTaskInfo), pSource->addr.nodeId, pSource->taskId, pExchangeInfo->current + 1,
-             pDataInfo->totalRows, pExchangeInfo->totalRows);
+             pDataInfo->totalRows, pLoadInfo->totalRows);
 
       pDataInfo->status = EX_SOURCE_DATA_EXHAUSTED;
       pExchangeInfo->current += 1;
@@ -5150,20 +5156,22 @@ static SSDataBlock* seqLoadRemoteData(SOperatorInfo *pOperator) {
     }
 
     SSDataBlock* pRes = pExchangeInfo->pResult;
-    setSDataBlockFromFetchRsp(pExchangeInfo->pResult, pExchangeInfo, pDataInfo, pOperator->numOfOutput, startTs);
+    SRetrieveTableRsp* pTableRsp = pDataInfo->pRsp;
+    int32_t code = setSDataBlockFromFetchRsp(pExchangeInfo->pResult, pLoadInfo, pTableRsp->numOfRows,
+                                             pTableRsp->data, pTableRsp->compLen, pOperator->numOfOutput, startTs, &pDataInfo->totalRows);
 
     if (pRsp->completed == 1) {
       qDebug("%s fetch msg rsp from vgId:%d, taskId:0x%" PRIx64 " numOfRows:%d, rowsOfSource:%" PRIu64
                  ", totalRows:%" PRIu64 ", totalBytes:%" PRIu64 " try next %d/%" PRIzu,
              GET_TASKID(pTaskInfo), pSource->addr.nodeId, pSource->taskId, pRes->info.rows,
-             pDataInfo->totalRows, pExchangeInfo->totalRows, pExchangeInfo->totalSize, pExchangeInfo->current + 1,
+             pDataInfo->totalRows, pLoadInfo->totalRows, pLoadInfo->totalSize, pExchangeInfo->current + 1,
              totalSources);
 
       pDataInfo->status = EX_SOURCE_DATA_EXHAUSTED;
       pExchangeInfo->current += 1;
     } else {
       qDebug("%s fetch msg rsp from vgId:%d, taskId:0x%" PRIx64 " numOfRows:%d, totalRows:%" PRIu64 ", totalBytes:%" PRIu64,
-             GET_TASKID(pTaskInfo), pSource->addr.nodeId, pSource->taskId, pRes->info.rows, pExchangeInfo->totalRows, pExchangeInfo->totalSize);
+             GET_TASKID(pTaskInfo), pSource->addr.nodeId, pSource->taskId, pRes->info.rows, pLoadInfo->totalRows, pLoadInfo->totalSize);
     }
 
     return pExchangeInfo->pResult;
@@ -5196,16 +5204,13 @@ static SSDataBlock* doLoadRemoteData(void* param, bool* newgroup) {
   SExchangeInfo *pExchangeInfo = pOperator->info;
   SExecTaskInfo *pTaskInfo = pOperator->pTaskInfo;
 
-  int32_t code = pOperator->_openFn(pOperator);
-  if (code != TSDB_CODE_SUCCESS) {
-    pTaskInfo->code = code;
-    return NULL;
-  }
+  size_t totalSources = taosArrayGetSize(pExchangeInfo->pSources);
+  SLoadRemoteDataInfo* pLoadInfo = &pExchangeInfo->loadInfo;
 
   size_t totalSources = taosArrayGetSize(pExchangeInfo->pSources);
   if (pOperator->status == OP_EXEC_DONE) {
     qDebug("%s all %"PRIzu" source(s) are exhausted, total rows:%"PRIu64" bytes:%"PRIu64", elapsed:%.2f ms", GET_TASKID(pTaskInfo), totalSources,
-           pExchangeInfo->totalRows, pExchangeInfo->totalSize, pExchangeInfo->totalElapsed/1000.0);
+           pLoadInfo->totalRows, pLoadInfo->totalSize, pLoadInfo->totalElapsed/1000.0);
     return NULL;
   }
 
@@ -5483,18 +5488,16 @@ SOperatorInfo* createStreamScanOperatorInfo(void *streamReadHandle, SSDataBlock*
   return pOperator;
 }
 
-
 static int32_t loadSysTableContentCb(void* param, const SDataBuf* pMsg, int32_t code) {
-  SSourceDataInfo* pSourceDataInfo = (SSourceDataInfo*) param;
-  pSourceDataInfo->pRsp = pMsg->pData;
+  SSysTableScanInfo* pScanResInfo = (SSysTableScanInfo*) param;
+  pScanResInfo->pRsp = pMsg->pData;
 
-  SRetrieveTableRsp* pRsp = pSourceDataInfo->pRsp;
+  SRetrieveMetaTableRsp* pRsp = pScanResInfo->pRsp;
   pRsp->numOfRows = htonl(pRsp->numOfRows);
   pRsp->useconds  = htobe64(pRsp->useconds);
+  pRsp->handle    = htobe64(pRsp->handle);
   pRsp->compLen   = htonl(pRsp->compLen);
-
-  pSourceDataInfo->status = EX_SOURCE_DATA_READY;
-  tsem_post(&pSourceDataInfo->pEx->ready);
+  tsem_post(&pScanResInfo->ready);
 }
 
 static SSDataBlock* doSysTableScan(void* param, bool* newgroup) {
@@ -5521,22 +5524,19 @@ static SSDataBlock* doSysTableScan(void* param, bool* newgroup) {
       }
     }
 
-    pInfo->totalRows += numOfRows;
+    pInfo->loadInfo.totalRows += numOfRows;
     pInfo->pRes->info.rows = numOfRows;
 
 //    pInfo->elapsedTime;
 //    pInfo->totalBytes;
     return (pInfo->pRes->info.rows == 0)? NULL:pInfo->pRes;
   } else {  // load the meta from mnode of the given epset
-    if (pInfo->pReq == NULL) {
-      pInfo->pReq = calloc(1, sizeof(SRetrieveTableReq));
-      if (pInfo->pReq == NULL) {
-        pTaskInfo->code = TSDB_CODE_OUT_OF_MEMORY;
-        return NULL;
-      }
+    int64_t startTs = taosGetTimestampUs();
 
-      pInfo->pReq->type = pInfo->type;
-    }
+    pInfo->req.type = pInfo->type;
+    int32_t contLen = tSerializeSRetrieveTableReq(NULL, 0, &pInfo->req);
+    char* buf1 = calloc(1, contLen);
+    tSerializeSRetrieveTableReq(buf1, contLen, &pInfo->req);
 
     // send the fetch remote task result reques
     SMsgSendInfo* pMsgSendInfo = calloc(1, sizeof(SMsgSendInfo));
@@ -5546,24 +5546,38 @@ static SSDataBlock* doSysTableScan(void* param, bool* newgroup) {
       return NULL;
     }
 
-    pMsgSendInfo->param = NULL;
-    pMsgSendInfo->msgInfo.pData = pInfo->pReq;
-    pMsgSendInfo->msgInfo.len = sizeof(SRetrieveTableReq);
+    pMsgSendInfo->param = pInfo;
+    pMsgSendInfo->msgInfo.pData = buf1;
+    pMsgSendInfo->msgInfo.len = contLen;
     pMsgSendInfo->msgType = TDMT_MND_SYSTABLE_RETRIEVE;
-    pMsgSendInfo->fp = loadRemoteDataCallback;
+    pMsgSendInfo->fp = loadSysTableContentCb;
 
     int64_t transporterId = 0;
     int32_t code = asyncSendMsgToServer(pInfo->pTransporter, &pInfo->epSet, &transporterId, pMsgSendInfo);
-
     tsem_wait(&pInfo->ready);
-    // handle the response and return to the caller
+
+    SRetrieveMetaTableRsp* pRsp = pInfo->pRsp;
+    pInfo->req.showId = pRsp->handle;
+
+    if (pRsp->numOfRows == 0) {
+//      qDebug("%s vgId:%d, taskID:0x%"PRIx64" %d of total completed, rowsOfSource:%"PRIu64", totalRows:%"PRIu64" try next",
+//             GET_TASKID(pTaskInfo), pSource->addr.nodeId, pSource->taskId, pExchangeInfo->current + 1,
+//             pDataInfo->totalRows, pExchangeInfo->totalRows);
+      return NULL;
+    }
+
+    SRetrieveMetaTableRsp* pTableRsp = pInfo->pRsp;
+    setSDataBlockFromFetchRsp(pInfo->pRes, &pInfo->loadInfo, pTableRsp->numOfRows,
+                              pTableRsp->data, pTableRsp->compLen, pOperator->numOfOutput, startTs, NULL);
+
+    return pInfo->pRes;
   }
 
   return NULL;
 }
 
-SOperatorInfo* createSysTableScanOperatorInfo(void* pSysTableReadHandle, const SArray* pExprInfo, const SSchema* pSchema,
-    int32_t tableType, SEpSet epset, SExecTaskInfo* pTaskInfo) {
+SOperatorInfo* createSysTableScanOperatorInfo(void* pSysTableReadHandle, SSDataBlock* pResBlock, int32_t tableType,
+                                              SEpSet epset, SExecTaskInfo* pTaskInfo) {
   SSysTableScanInfo* pInfo = calloc(1, sizeof(SSysTableScanInfo));
   SOperatorInfo* pOperator = calloc(1, sizeof(SOperatorInfo));
   if (pInfo == NULL || pOperator == NULL) {
@@ -5573,7 +5587,7 @@ SOperatorInfo* createSysTableScanOperatorInfo(void* pSysTableReadHandle, const S
     return NULL;
   }
 
-  // todo: create the schema of result data block
+  pInfo->pRes     = pResBlock;
   pInfo->capacity = 4096;
   pInfo->type     = tableType;
   if (pInfo->type == TSDB_MGMT_TABLE_TABLE) {
@@ -5590,70 +5604,35 @@ SOperatorInfo* createSysTableScanOperatorInfo(void* pSysTableReadHandle, const S
   pOperator->blockingOptr  = false;
   pOperator->status        = OP_IN_EXECUTING;
   pOperator->info          = pInfo;
-  pOperator->numOfOutput   = taosArrayGetSize(pExprInfo);
-  pOperator->getNextFn     = doSysTableScan;
+  pOperator->numOfOutput   = pResBlock->info.numOfCols;
+  pOperator->nextDataFn    = doSysTableScan;
   pOperator->closeFn       = destroySysTableScannerOperatorInfo;
   pOperator->pTaskInfo     = pTaskInfo;
 
-  return pOperator;
-}
-
-void setTableScanFilterOperatorInfo(STableScanInfo* pTableScanInfo, SOperatorInfo* pDownstream) {
-  assert(pTableScanInfo != NULL && pDownstream != NULL);
+#if 1
+  { // todo refactor
+    SRpcInit rpcInit;
+    memset(&rpcInit, 0, sizeof(rpcInit));
+    rpcInit.localPort = 0;
+    rpcInit.label = "DB-META";
+    rpcInit.numOfThreads = 1;
+    rpcInit.cfp = qProcessFetchRsp;
+    rpcInit.sessions = tsMaxConnections;
+    rpcInit.connType = TAOS_CONN_CLIENT;
+    rpcInit.user = (char *)"root";
+    rpcInit.idleTime = tsShellActivityTimer * 1000;
+    rpcInit.ckey = "key";
+    rpcInit.spi = 1;
+    rpcInit.secret = (char *)"dcc5bed04851fec854c035b2e40263b6";
 
-  pTableScanInfo->pExpr = pDownstream->pExpr;   // TODO refactor to use colId instead of pExpr
-  pTableScanInfo->numOfOutput = pDownstream->numOfOutput;
-#if 0
-  if (pDownstream->operatorType == OP_Aggregate || pDownstream->operatorType == OP_MultiTableAggregate) {
-    SAggOperatorInfo* pAggInfo = pDownstream->info;
-
-    pTableScanInfo->pCtx = pAggInfo->binfo.pCtx;
-    pTableScanInfo->pResultRowInfo = &pAggInfo->binfo.resultRowInfo;
-    pTableScanInfo->rowCellInfoOffset = pAggInfo->binfo.rowCellInfoOffset;
-  } else if (pDownstream->operatorType == OP_TimeWindow || pDownstream->operatorType == OP_AllTimeWindow) {
-    STableIntervalOperatorInfo *pIntervalInfo = pDownstream->info;
-
-    pTableScanInfo->pCtx = pIntervalInfo->pCtx;
-    pTableScanInfo->pResultRowInfo = &pIntervalInfo->resultRowInfo;
-    pTableScanInfo->rowCellInfoOffset = pIntervalInfo->rowCellInfoOffset;
-
-  } else if (pDownstream->operatorType == OP_Groupby) {
-    SGroupbyOperatorInfo *pGroupbyInfo = pDownstream->info;
-
-    pTableScanInfo->pCtx = pGroupbyInfo->binfo.pCtx;
-    pTableScanInfo->pResultRowInfo = &pGroupbyInfo->binfo.resultRowInfo;
-    pTableScanInfo->rowCellInfoOffset = pGroupbyInfo->binfo.rowCellInfoOffset;
-
-  } else if (pDownstream->operatorType == OP_MultiTableTimeInterval || pDownstream->operatorType == OP_AllMultiTableTimeInterval) {
-    STableIntervalOperatorInfo *pInfo = pDownstream->info;
-
-    pTableScanInfo->pCtx = pInfo->pCtx;
-    pTableScanInfo->pResultRowInfo = &pInfo->resultRowInfo;
-    pTableScanInfo->rowCellInfoOffset = pInfo->rowCellInfoOffset;
-
-  } else if (pDownstream->operatorType == OP_Project) {
-    SProjectOperatorInfo *pInfo = pDownstream->info;
-
-    pTableScanInfo->pCtx = pInfo->binfo.pCtx;
-    pTableScanInfo->pResultRowInfo = &pInfo->binfo.resultRowInfo;
-    pTableScanInfo->rowCellInfoOffset = pInfo->binfo.rowCellInfoOffset;
-  } else if (pDownstream->operatorType == OP_SessionWindow) {
-    SSWindowOperatorInfo* pInfo = pDownstream->info;
-
-    pTableScanInfo->pCtx = pInfo->binfo.pCtx;
-    pTableScanInfo->pResultRowInfo = &pInfo->binfo.resultRowInfo;
-    pTableScanInfo->rowCellInfoOffset = pInfo->binfo.rowCellInfoOffset;
-  } else if (pDownstream->operatorType == OP_StateWindow) {
-    SStateWindowOperatorInfo* pInfo = pDownstream->info;
-
-    pTableScanInfo->pCtx = pInfo->binfo.pCtx;
-    pTableScanInfo->pResultRowInfo = &pInfo->binfo.resultRowInfo;
-    pTableScanInfo->rowCellInfoOffset = pInfo->binfo.rowCellInfoOffset;
-  } else {
-    assert(0);
+    pInfo->pTransporter = rpcOpen(&rpcInit);
+    if (pInfo->pTransporter == NULL) {
+      return NULL; // todo
+    }
   }
 #endif
 
+  return pOperator;
 }
 
 SArray* getOrderCheckColumns(STaskAttr* pQuery) {
@@ -7355,23 +7334,23 @@ SOperatorInfo* createMultiTableAggOperatorInfo(SOperatorInfo* downstream, SArray
 SOperatorInfo* createProjectOperatorInfo(SOperatorInfo* downstream, SArray* pExprInfo, SExecTaskInfo* pTaskInfo) {
   SProjectOperatorInfo* pInfo = calloc(1, sizeof(SProjectOperatorInfo));
 
-  int32_t numOfRows = 4096;
-  pInfo->binfo.pRes = createOutputBuf_rv(pExprInfo, numOfRows);
+  pInfo->binfo.capacity = 4096;
+  pInfo->binfo.pRes = createOutputBuf_rv(pExprInfo, pInfo->binfo.capacity);
   pInfo->binfo.pCtx = createSqlFunctionCtx_rv(pExprInfo, &pInfo->binfo.rowCellInfoOffset);
-
 //  initResultRowInfo(&pBInfo->resultRowInfo, 8);
 //  setFunctionResultOutput(pBInfo, MAIN_SCAN);
 
   SOperatorInfo* pOperator = calloc(1, sizeof(SOperatorInfo));
   pOperator->name         = "ProjectOperator";
-  // pOperator->operatorType = OP_Project;
+  pOperator->operatorType = QUERY_NODE_PHYSICAL_PLAN_PROJECT;
   pOperator->blockingOptr = false;
   pOperator->status       = OP_NOT_OPENED;
   pOperator->info         = pInfo;
   pOperator->pExpr        = exprArrayDup(pExprInfo);
   pOperator->numOfOutput  = taosArrayGetSize(pExprInfo);
 
-  pOperator->getNextFn   = doProjectOperation;
+  pOperator->nextDataFn   = doProjectOperation;
+  pOperator->pTaskInfo    = pTaskInfo;
   pOperator->closeFn      = destroyProjectOperatorInfo;
   int32_t code = appendDownstream(pOperator, &downstream, 1);
 
@@ -8039,37 +8018,6 @@ bool validateExprColumnInfo(SQueriedTableInfo *pTableInfo, SExprBasicInfo *pExpr
   return j != INT32_MIN;
 }
 
-static bool validateQueryTableCols(SQueriedTableInfo* pTableInfo, SExprBasicInfo** pExpr, int32_t numOfOutput,
-                                   SColumnInfo* pTagCols, void* pMsg) {
-  int32_t numOfTotal = pTableInfo->numOfCols + pTableInfo->numOfTags;
-  if (pTableInfo->numOfCols < 0 || pTableInfo->numOfTags < 0 || numOfTotal > TSDB_MAX_COLUMNS) {
-    //qError("qmsg:%p illegal value of numOfCols %d numOfTags:%d", pMsg, pTableInfo->numOfCols, pTableInfo->numOfTags);
-    return false;
-  }
-
-  if (numOfTotal == 0) {  // table total columns are not required.
-//    for(int32_t i = 0; i < numOfOutput; ++i) {
-//      SExprBasicInfo* p = pExpr[i];
-//      if ((p->functionId == FUNCTION_TAGPRJ) ||
-//          (p->functionId == FUNCTION_TID_TAG && p->colInfo.colId == TSDB_TBNAME_COLUMN_INDEX) ||
-//          (p->functionId == FUNCTION_COUNT && p->colInfo.colId == TSDB_TBNAME_COLUMN_INDEX) ||
-//          (p->functionId == FUNCTION_BLKINFO)) {
-//        continue;
-//      }
-//
-//      return false;
-//    }
-  }
-
-  for(int32_t i = 0; i < numOfOutput; ++i) {
-    if (!validateExprColumnInfo(pTableInfo, pExpr[i], pTagCols)) {
-      return TSDB_CODE_QRY_INVALID_MSG;
-    }
-  }
-
-  return true;
-}
-
 static int32_t deserializeColFilterInfo(SColumnFilterInfo* pColFilters, int16_t numOfFilters, char** pMsg) {
   for (int32_t f = 0; f < numOfFilters; ++f) {
     SColumnFilterInfo *pFilterMsg = (SColumnFilterInfo *)(*pMsg);
@@ -8104,10 +8052,10 @@ static int32_t deserializeColFilterInfo(SColumnFilterInfo* pColFilters, int16_t
 static SResSchema createResSchema(int32_t type, int32_t bytes, int32_t slotId, int32_t scale, int32_t precision, const char* name) {
   SResSchema s = {0};
   s.scale = scale;
-  s.precision = precision;
   s.type  = type;
   s.bytes = bytes;
   s.colId = slotId;
+  s.precision = precision;
   strncpy(s.name, name, tListLen(s.name));
 
   return s;
@@ -8243,9 +8191,16 @@ SOperatorInfo* doCreateOperatorTreeNode(SPhysiNode* pPhyNode, SExecTaskInfo* pTa
       SArray* colList = extractScanColumnId(pScanPhyNode->pScanCols);
 
       SOperatorInfo* pOperator = createStreamScanOperatorInfo(pHandle->reader, pResBlock, colList, tableIdList, pTaskInfo);
-
       taosArrayDestroy(tableIdList);
       return pOperator;
+    } else if (QUERY_NODE_PHYSICAL_PLAN_SYSTABLE_SCAN == nodeType(pPhyNode)) {
+      SSystemTableScanPhysiNode * pSysScanPhyNode = (SSystemTableScanPhysiNode*)pPhyNode;
+      SSDataBlock* pResBlock = createOutputBuf_rv1(pSysScanPhyNode->scan.node.pOutputDataBlockDesc);
+
+      SOperatorInfo* pOperator = createSysTableScanOperatorInfo(NULL, pResBlock,  TSDB_MGMT_TABLE_DB, pSysScanPhyNode->mgmtEpSet, pTaskInfo);
+      return pOperator;
+    } else {
+      ASSERT(0);
     }
   }
 

source/libs/function/inc/builtinsimpl.h

@@ -37,6 +37,10 @@ bool getMinmaxFuncEnv(SFunctionNode* pFunc, SFuncExecEnv* pEnv);
 void minFunction(SqlFunctionCtx* pCtx);
 void maxFunction(SqlFunctionCtx *pCtx);
 
+bool getFirstLastFuncEnv(SFunctionNode* pFunc, SFuncExecEnv* pEnv);
+void firstFunction(SqlFunctionCtx *pCtx);
+void lastFunction(SqlFunctionCtx *pCtx);
+
 #ifdef __cplusplus
 }
 #endif

source/libs/function/src/builtins.c

@@ -61,6 +61,26 @@ const SBuiltinFuncDefinition funcMgtBuiltins[] = {
     .processFunc  = maxFunction,
     .finalizeFunc = functionFinalizer
   },
+  {
+    .name = "first",
+    .type = FUNCTION_TYPE_FIRST,
+    .classification = FUNC_MGT_AGG_FUNC,
+    .checkFunc    = stubCheckAndGetResultType,
+    .getEnvFunc   = getFirstLastFuncEnv,
+    .initFunc     = functionSetup,
+    .processFunc  = firstFunction,
+    .finalizeFunc = functionFinalizer
+  },
+  {
+    .name = "last",
+    .type = FUNCTION_TYPE_LAST,
+    .classification = FUNC_MGT_AGG_FUNC,
+    .checkFunc    = stubCheckAndGetResultType,
+    .getEnvFunc   = getFirstLastFuncEnv,
+    .initFunc     = functionSetup,
+    .processFunc  = lastFunction,
+    .finalizeFunc = functionFinalizer
+  },
   {
     .name = "concat",
     .type = FUNCTION_TYPE_CONCAT,
@@ -98,6 +118,8 @@ int32_t stubCheckAndGetResultType(SFunctionNode* pFunc) {
       pFunc->node.resType = (SDataType) { .bytes = tDataTypes[resType].bytes, .type = resType };
       break;
     }
+    case FUNCTION_TYPE_FIRST:
+    case FUNCTION_TYPE_LAST:
     case FUNCTION_TYPE_MIN:
     case FUNCTION_TYPE_MAX: {
       SColumnNode* pParam = nodesListGetNode(pFunc->pParameterList, 0);

source/libs/function/src/builtinsimpl.c

@@ -72,13 +72,12 @@ void countFunction(SqlFunctionCtx *pCtx) {
   int32_t numOfElem = 0;
 
   /*
-   * 1. column data missing (schema modified) causes pCtx->hasNull == true. pCtx->isAggSet == true;
-   * 2. for general non-primary key columns, pCtx->hasNull may be true or false, pCtx->isAggSet == true;
-   * 3. for primary key column, pCtx->hasNull always be false, pCtx->isAggSet == false;
+   * 1. column data missing (schema modified) causes pInputCol->hasNull == true. pInput->colDataAggIsSet == true;
+   * 2. for general non-primary key columns, pInputCol->hasNull may be true or false, pInput->colDataAggIsSet == true;
+   * 3. for primary key column, pInputCol->hasNull always be false, pInput->colDataAggIsSet == false;
    */
   SInputColumnInfoData* pInput = &pCtx->input;
   SColumnInfoData* pInputCol = pInput->pData[0];
-
   if (pInput->colDataAggIsSet && pInput->totalRows == pInput->numOfRows) {
     numOfElem = pInput->numOfRows - pInput->pColumnDataAgg[0]->numOfNull;
     ASSERT(numOfElem >= 0);
@@ -173,7 +172,7 @@ void sumFunction(SqlFunctionCtx *pCtx) {
   SET_VAL(GET_RES_INFO(pCtx), numOfElem, 1);
 }
 
-bool getSumFuncEnv(SFunctionNode* pFunc, SFuncExecEnv* pEnv) {
+bool getSumFuncEnv(SFunctionNode* UNUSED_PARAM(pFunc), SFuncExecEnv* pEnv) {
   pEnv->calcMemSize = sizeof(SSumRes);
   return true;
 }
@@ -265,8 +264,7 @@ bool minFunctionSetup(SqlFunctionCtx *pCtx, SResultRowEntryInfo* pResultInfo) {
   return true;
 }
 
-bool getMinmaxFuncEnv(SFunctionNode* pFunc, SFuncExecEnv* pEnv) {
-  SNode* pNode = nodesListGetNode(pFunc->pParameterList, 0);
+bool getMinmaxFuncEnv(SFunctionNode* UNUSED_PARAM(pFunc), SFuncExecEnv* pEnv) {
   pEnv->calcMemSize = sizeof(int64_t);
   return true;
 }
@@ -278,34 +276,34 @@ bool getMinmaxFuncEnv(SFunctionNode* pFunc, SFuncExecEnv* pEnv) {
   do {                                                             \
     for (int32_t _i = 0; _i < (ctx)->tagInfo.numOfTagCols; ++_i) { \
       SqlFunctionCtx *__ctx = (ctx)->tagInfo.pTagCtxList[_i];      \
-      __ctx->fpSet.process(__ctx);                       \
+      __ctx->fpSet.process(__ctx);                                 \
     }                                                              \
   } while (0);
 
-#define DO_UPDATE_SUBSID_RES(ctx, ts)                             \
-  do {                                                             \
+#define DO_UPDATE_SUBSID_RES(ctx, ts)                                 \
+  do {                                                                \
     for (int32_t _i = 0; _i < (ctx)->subsidiaryRes.numOfCols; ++_i) { \
-      SqlFunctionCtx *__ctx = (ctx)->subsidiaryRes.pCtx[_i];      \
-      if (__ctx->functionId == FUNCTION_TS_DUMMY) {                \
-        __ctx->tag.i = (ts);                                       \
-        __ctx->tag.nType = TSDB_DATA_TYPE_BIGINT;                  \
-      }                                                            \
-      __ctx->fpSet.process(__ctx);                                 \
-    }                                                              \
+      SqlFunctionCtx *__ctx = (ctx)->subsidiaryRes.pCtx[_i];          \
+      if (__ctx->functionId == FUNCTION_TS_DUMMY) {                   \
+        __ctx->tag.i = (ts);                                          \
+        __ctx->tag.nType = TSDB_DATA_TYPE_BIGINT;                     \
+      }                                                               \
+      __ctx->fpSet.process(__ctx);                                    \
+    }                                                                 \
   } while (0)
 
 #define UPDATE_DATA(ctx, left, right, num, sign, _ts) \
-  do {                                              \
-    if (((left) < (right)) ^ (sign)) {              \
-      (left) = (right);                             \
-      DO_UPDATE_SUBSID_RES(ctx, _ts);                \
-      (num) += 1;                                   \
-    }                                               \
+  do {                                                \
+    if (((left) < (right)) ^ (sign)) {                \
+      (left) = (right);                               \
+      DO_UPDATE_SUBSID_RES(ctx, _ts);                 \
+      (num) += 1;                                     \
+    }                                                 \
   } while (0)
 
-#define LOOPCHECK_N(val, _col, ctx, _t, _nrow, _start, sign, num)       \
+#define LOOPCHECK_N(val, _col, ctx, _t, _nrow, _start, sign, num)        \
   do {                                                                   \
-    _t* d = (_t*)((_col)->pData);                                        \
+    _t *d = (_t *)((_col)->pData);                                       \
     for (int32_t i = (_start); i < (_nrow) + (_start); ++i) {            \
       if (((_col)->hasNull) && colDataIsNull_f((_col)->nullbitmap, i)) { \
         continue;                                                        \
@@ -445,4 +443,118 @@ void minFunction(SqlFunctionCtx *pCtx) {
 void maxFunction(SqlFunctionCtx *pCtx) {
   int32_t numOfElems = doMinMaxHelper(pCtx, 0);
   SET_VAL(GET_RES_INFO(pCtx), numOfElems, 1);
-}
\ No newline at end of file
+}
+
+bool getFirstLastFuncEnv(SFunctionNode* pFunc, SFuncExecEnv* pEnv) {
+  SColumnNode* pNode = nodesListGetNode(pFunc->pParameterList, 0);
+  pEnv->calcMemSize = pNode->node.resType.bytes;
+  return true;
+}
+
+// TODO fix this
+// This ordinary first function only handle the data block in ascending order
+void firstFunction(SqlFunctionCtx *pCtx) {
+  if (pCtx->order == TSDB_ORDER_DESC) {
+    return;
+  }
+
+  int32_t numOfElems = 0;
+
+  struct SResultRowEntryInfo *pResInfo = GET_RES_INFO(pCtx);
+  char* buf = GET_ROWCELL_INTERBUF(pResInfo);
+
+  SInputColumnInfoData* pInput = &pCtx->input;
+
+  SColumnInfoData* pInputCol = pInput->pData[0];
+
+  // All null data column, return directly.
+  if (pInput->pColumnDataAgg[0]->numOfNull == pInput->totalRows) {
+    ASSERT(pInputCol->hasNull == true);
+    return;
+  }
+
+  // Check for the first not null data
+  for (int32_t i = pInput->startRowIndex; i < pInput->numOfRows + pInput->startRowIndex; ++i) {
+    if (pInputCol->hasNull && colDataIsNull(pInputCol, pInput->totalRows, i, NULL)) {
+      continue;
+    }
+
+    char* data = colDataGetData(pInputCol, i);
+    memcpy(buf, data, pInputCol->info.bytes);
+    // TODO handle the subsidary value
+//    if (pCtx->ptsList != NULL) {
+//      TSKEY k = GET_TS_DATA(pCtx, i);
+//      DO_UPDATE_TAG_COLUMNS(pCtx, k);
+//    }
+
+    pResInfo->hasResult = DATA_SET_FLAG;
+    pResInfo->complete = true;
+
+    numOfElems++;
+    break;
+  }
+
+  SET_VAL(pResInfo, numOfElems, 1);
+}
+
+void lastFunction(SqlFunctionCtx *pCtx) {
+  if (pCtx->order != TSDB_ORDER_DESC) {
+    return;
+  }
+
+  int32_t numOfElems = 0;
+
+  struct SResultRowEntryInfo *pResInfo = GET_RES_INFO(pCtx);
+  char* buf = GET_ROWCELL_INTERBUF(pResInfo);
+
+  SInputColumnInfoData* pInput = &pCtx->input;
+
+  SColumnInfoData* pInputCol = pInput->pData[0];
+
+  // All null data column, return directly.
+  if (pInput->pColumnDataAgg[0]->numOfNull == pInput->totalRows) {
+    ASSERT(pInputCol->hasNull == true);
+    return;
+  }
+
+  if (pCtx->order == TSDB_ORDER_DESC) {
+    for (int32_t i = pInput->numOfRows + pInput->startRowIndex - 1; i >= pInput->startRowIndex; --i) {
+      if (pInputCol->hasNull && colDataIsNull(pInputCol, pInput->totalRows, i, NULL)) {
+        continue;
+      }
+
+      char* data = colDataGetData(pInputCol, i);
+      memcpy(buf, data, pInputCol->info.bytes);
+
+//      TSKEY ts = pCtx->ptsList ? GET_TS_DATA(pCtx, i) : 0;
+//      DO_UPDATE_TAG_COLUMNS(pCtx, ts);
+
+      pResInfo->hasResult = DATA_SET_FLAG;
+      pResInfo->complete = true;  // set query completed on this column
+      numOfElems++;
+      break;
+    }
+  } else {  // ascending order
+    for (int32_t i = pInput->startRowIndex; i < pInput->numOfRows + pInput->startRowIndex; ++i) {
+      if (pInputCol->hasNull && colDataIsNull(pInputCol, pInput->totalRows, i, NULL)) {
+        continue;
+      }
+
+      char* data = colDataGetData(pInputCol, i);
+      TSKEY ts = pCtx->ptsList ? GET_TS_DATA(pCtx, i) : 0;
+
+      if (pResInfo->hasResult != DATA_SET_FLAG || (*(TSKEY*)buf) < ts) {
+        pResInfo->hasResult = DATA_SET_FLAG;
+        memcpy(buf, data, pCtx->inputBytes);
+
+        *(TSKEY*)buf = ts;
+//        DO_UPDATE_TAG_COLUMNS(pCtx, ts);
+      }
+
+      numOfElems++;
+      break;
+    }
+  }
+
+  SET_VAL(pResInfo, numOfElems, 1);
+}

source/libs/nodes/src/nodesCodeFuncs.c

@@ -107,6 +107,8 @@ const char* nodesNodeName(ENodeType type) {
       return "PhysiTableSeqScan";
     case QUERY_NODE_PHYSICAL_PLAN_STREAM_SCAN:
       return "PhysiSreamScan";
+    case QUERY_NODE_PHYSICAL_PLAN_SYSTABLE_SCAN:
+      return "PhysiSystemTableScan";
     case QUERY_NODE_PHYSICAL_PLAN_PROJECT:
       return "PhysiProject";
     case QUERY_NODE_PHYSICAL_PLAN_JOIN:
@@ -440,6 +442,87 @@ static int32_t jsonToPhysiTableScanNode(const SJson* pJson, void* pObj) {
   return code;
 }
 
+static const char* jkEndPointFqdn = "Fqdn";
+static const char* jkEndPointPort = "Port";
+
+static int32_t epToJson(const void* pObj, SJson* pJson) {
+  const SEp* pNode = (const SEp*)pObj;
+
+  int32_t code = tjsonAddStringToObject(pJson, jkEndPointFqdn, pNode->fqdn);
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonAddIntegerToObject(pJson, jkEndPointPort, pNode->port);
+  }
+
+  return code;
+}
+
+static int32_t jsonToEp(const SJson* pJson, void* pObj) {
+  SEp* pNode = (SEp*)pObj;
+
+  int32_t code = tjsonGetStringValue(pJson, jkEndPointFqdn, pNode->fqdn);
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonGetSmallIntValue(pJson, jkEndPointPort, &pNode->port);
+  }
+
+  return code;
+}
+
+static const char* jkEpSetInUse = "InUse";
+static const char* jkEpSetNumOfEps = "NumOfEps";
+static const char* jkEpSetEps = "Eps";
+
+static int32_t epSetToJson(const void* pObj, SJson* pJson) {
+  const SEpSet* pNode = (const SEpSet*)pObj;
+
+  int32_t code = tjsonAddIntegerToObject(pJson, jkEpSetInUse, pNode->inUse);
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonAddIntegerToObject(pJson, jkEpSetNumOfEps, pNode->numOfEps);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonAddArray(pJson, jkEpSetEps, epToJson, pNode->eps, sizeof(SEp), pNode->numOfEps);
+  }
+
+  return code;
+}
+
+static int32_t jsonToEpSet(const SJson* pJson, void* pObj) {
+  SEpSet* pNode = (SEpSet*)pObj;
+
+  int32_t code = tjsonGetTinyIntValue(pJson, jkEpSetInUse, &pNode->inUse);
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonGetTinyIntValue(pJson, jkEpSetNumOfEps, &pNode->numOfEps);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonToArray(pJson, jkEpSetEps, jsonToEp, pNode->eps, sizeof(SEp));
+  }
+
+  return code;
+}
+
+static const char* jkSysTableScanPhysiPlanMnodeEpSet = "MnodeEpSet";
+
+static int32_t physiSysTableScanNodeToJson(const void* pObj, SJson* pJson) {
+  const SSystemTableScanPhysiNode* pNode = (const SSystemTableScanPhysiNode*)pObj;
+
+  int32_t code = physiScanNodeToJson(pObj, pJson);
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonAddObject(pJson, jkSysTableScanPhysiPlanMnodeEpSet, epSetToJson, &pNode->mgmtEpSet);
+  }
+
+  return code;
+}
+
+static int32_t jsonToPhysiSysTableScanNode(const SJson* pJson, void* pObj) {
+  SSystemTableScanPhysiNode* pNode = (SSystemTableScanPhysiNode*)pObj;
+
+  int32_t code = jsonToPhysiScanNode(pJson, pObj);
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonToObject(pJson, jkSysTableScanPhysiPlanMnodeEpSet, jsonToEpSet, &pNode->mgmtEpSet);
+  }
+
+  return code;
+}
+
 static const char* jkProjectPhysiPlanProjections = "Projections";
 
 static int32_t physiProjectNodeToJson(const void* pObj, SJson* pJson) {
@@ -625,31 +708,6 @@ static int32_t jsonToSubplanId(const SJson* pJson, void* pObj) {
   return code;
 }
 
-static const char* jkEndPointFqdn = "Fqdn";
-static const char* jkEndPointPort = "Port";
-
-static int32_t epToJson(const void* pObj, SJson* pJson) {
-  const SEp* pNode = (const SEp*)pObj;
-
-  int32_t code = tjsonAddStringToObject(pJson, jkEndPointFqdn, pNode->fqdn);
-  if (TSDB_CODE_SUCCESS == code) {
-    code = tjsonAddIntegerToObject(pJson, jkEndPointPort, pNode->port);
-  }
-
-  return code;
-}
-
-static int32_t jsonToEp(const SJson* pJson, void* pObj) {
-  SEp* pNode = (SEp*)pObj;
-
-  int32_t code = tjsonGetStringValue(pJson, jkEndPointFqdn, pNode->fqdn);
-  if (TSDB_CODE_SUCCESS == code) {
-    code = tjsonGetSmallIntValue(pJson, jkEndPointPort, &pNode->port);
-  }
-
-  return code;
-}
-
 static const char* jkQueryNodeAddrId = "Id";
 static const char* jkQueryNodeAddrInUse = "InUse";
 static const char* jkQueryNodeAddrNumOfEps = "NumOfEps";
@@ -1490,6 +1548,8 @@ static int32_t specificNodeToJson(const void* pObj, SJson* pJson) {
     case QUERY_NODE_PHYSICAL_PLAN_TABLE_SEQ_SCAN:
     case QUERY_NODE_PHYSICAL_PLAN_STREAM_SCAN:
       break;
+    case QUERY_NODE_PHYSICAL_PLAN_SYSTABLE_SCAN:
+      return physiSysTableScanNodeToJson(pObj, pJson);
     case QUERY_NODE_PHYSICAL_PLAN_PROJECT:
       return physiProjectNodeToJson(pObj, pJson);
     case QUERY_NODE_PHYSICAL_PLAN_JOIN:
@@ -1567,6 +1627,8 @@ static int32_t jsonToSpecificNode(const SJson* pJson, void* pObj) {
       return jsonToPhysiTagScanNode(pJson, pObj);
     case QUERY_NODE_PHYSICAL_PLAN_TABLE_SCAN:
       return jsonToPhysiTableScanNode(pJson, pObj);
+    case QUERY_NODE_PHYSICAL_PLAN_SYSTABLE_SCAN:
+      return jsonToPhysiSysTableScanNode(pJson, pObj);
     case QUERY_NODE_PHYSICAL_PLAN_PROJECT:
       return jsonToPhysiProjectNode(pJson, pObj);
     case QUERY_NODE_PHYSICAL_PLAN_JOIN:

source/libs/nodes/src/nodesUtilFuncs.c

@@ -146,6 +146,8 @@ SNodeptr nodesMakeNode(ENodeType type) {
       return makeNode(type, sizeof(STableSeqScanPhysiNode));
     case QUERY_NODE_PHYSICAL_PLAN_STREAM_SCAN:
       return makeNode(type, sizeof(SNode));
+    case QUERY_NODE_PHYSICAL_PLAN_SYSTABLE_SCAN:
+      return makeNode(type, sizeof(SSystemTableScanPhysiNode));
     case QUERY_NODE_PHYSICAL_PLAN_PROJECT:
       return makeNode(type, sizeof(SProjectPhysiNode));
     case QUERY_NODE_PHYSICAL_PLAN_JOIN:

source/libs/parser/inc/parUtil.h

@@ -23,6 +23,13 @@ extern "C" {
 #include "os.h"
 #include "query.h"
 
+#define parserFatal(param, ...)  qFatal("PARSER: " param, __VA_ARGS__)
+#define parserError(param, ...)  qError("PARSER: " param, __VA_ARGS__)
+#define parserWarn(param, ...)   qWarn("PARSER: " param, __VA_ARGS__)
+#define parserInfo(param, ...)   qInfo("PARSER: " param, __VA_ARGS__)
+#define parserDebug(param, ...)  qDebug("PARSER: " param, __VA_ARGS__)
+#define parserTrace(param, ...)  qTrace("PARSER: " param, __VA_ARGS__)
+
 typedef struct SMsgBuf {
   int32_t len;
   char   *buf;

source/libs/parser/src/parAstCreater.c

@@ -396,9 +396,9 @@ static bool checkPort(SAstCreateContext* pCxt, const SToken* pPortToken, int32_t
   return pCxt->valid;
 }
 
-static bool checkDbName(SAstCreateContext* pCxt, const SToken* pDbName) {
+static bool checkDbName(SAstCreateContext* pCxt, const SToken* pDbName, bool query) {
   if (NULL == pDbName) {
-    return true;
+    return (query ? NULL != pCxt->pQueryCxt->db : true);
   }
   pCxt->valid = pDbName->n < TSDB_DB_NAME_LEN ? true : false;
   return pCxt->valid;
@@ -557,7 +557,7 @@ SNode* createNodeListNode(SAstCreateContext* pCxt, SNodeList* pList) {
 }
 
 SNode* createRealTableNode(SAstCreateContext* pCxt, const SToken* pDbName, const SToken* pTableName, const SToken* pTableAlias) {
-  if (!checkDbName(pCxt, pDbName) || !checkTableName(pCxt, pTableName)) {
+  if (!checkDbName(pCxt, pDbName, true) || !checkTableName(pCxt, pTableName)) {
     return NULL;
   }
   SRealTableNode* realTable = (SRealTableNode*)nodesMakeNode(QUERY_NODE_REAL_TABLE);
@@ -769,7 +769,7 @@ SDatabaseOptions* setDatabaseOption(SAstCreateContext* pCxt, SDatabaseOptions* p
 }
 
 SNode* createCreateDatabaseStmt(SAstCreateContext* pCxt, bool ignoreExists, const SToken* pDbName, SDatabaseOptions* pOptions) {
-  if (!checkDbName(pCxt, pDbName)) {
+  if (!checkDbName(pCxt, pDbName, false)) {
     return NULL;
   }
   SCreateDatabaseStmt* pStmt = (SCreateDatabaseStmt*)nodesMakeNode(QUERY_NODE_CREATE_DATABASE_STMT);
@@ -782,7 +782,7 @@ SNode* createCreateDatabaseStmt(SAstCreateContext* pCxt, bool ignoreExists, cons
 }
 
 SNode* createDropDatabaseStmt(SAstCreateContext* pCxt, bool ignoreNotExists, const SToken* pDbName) {
-  if (!checkDbName(pCxt, pDbName)) {
+  if (!checkDbName(pCxt, pDbName, false)) {
     return NULL;
   }
   SDropDatabaseStmt* pStmt = (SDropDatabaseStmt*)nodesMakeNode(QUERY_NODE_DROP_DATABASE_STMT);
@@ -904,7 +904,7 @@ SNode* createUseDatabaseStmt(SAstCreateContext* pCxt, const SToken* pDbName) {
 }
 
 SNode* createShowStmt(SAstCreateContext* pCxt, ENodeType type, const SToken* pDbName) {
-  if (!checkDbName(pCxt, pDbName)) {
+  if (!checkDbName(pCxt, pDbName, false)) {
     return NULL;
   }
   SShowStmt* pStmt = nodesMakeNode(type);;

source/libs/parser/src/parInsert.c

@@ -1032,7 +1032,6 @@ int32_t parseInsertSql(SParseContext* pContext, SQuery** pQuery) {
   };
 
   if (NULL == context.pVgroupsHashObj || NULL == context.pTableBlockHashObj || NULL == context.pOutput) {
-    terrno = TSDB_CODE_TSC_OUT_OF_MEMORY;
     return TSDB_CODE_TSC_OUT_OF_MEMORY;
   }
 
@@ -1051,6 +1050,5 @@ int32_t parseInsertSql(SParseContext* pContext, SQuery** pQuery) {
     code = parseInsertBody(&context);
   }
   destroyInsertParseContext(&context);
-  terrno = code;
   return code;
 }

source/libs/parser/src/parTranslater.c

@@ -69,14 +69,78 @@ static int32_t addNamespace(STranslateContext* pCxt, void* pTable) {
   return TSDB_CODE_SUCCESS;
 }
 
-static SName* toName(int32_t acctId, const SRealTableNode* pRealTable, SName* pName) {
+static SName* toName(int32_t acctId, const char* pDbName, const char* pTableName, SName* pName) {
   pName->type = TSDB_TABLE_NAME_T;
   pName->acctId = acctId;
-  strcpy(pName->dbname, pRealTable->table.dbName);
-  strcpy(pName->tname, pRealTable->table.tableName);
+  strcpy(pName->dbname, pDbName);
+  strcpy(pName->tname, pTableName);
   return pName;
 }
 
+static int32_t getTableMetaImpl(SParseContext* pCxt, const SName* pName, STableMeta** pMeta) {
+  int32_t code = catalogGetTableMeta(pCxt->pCatalog, pCxt->pTransporter, &pCxt->mgmtEpSet, pName, pMeta);
+  if (TSDB_CODE_SUCCESS != code) {
+    parserError("catalogGetTableMeta error, code:%s, dbName:%s, tbName:%s", tstrerror(code), pName->dbname, pName->tname);
+  }
+  return code;
+}
+
+static int32_t getTableMeta(SParseContext* pCxt, const char* pDbName, const char* pTableName, STableMeta** pMeta) {
+  SName name = { .type = TSDB_TABLE_NAME_T, .acctId = pCxt->acctId };
+  strcpy(name.dbname, pDbName);
+  strcpy(name.tname, pTableName);
+  return getTableMetaImpl(pCxt, &name, pMeta);
+}
+
+static int32_t getTableDistVgInfo(SParseContext* pCxt, const SName* pName, SArray** pVgInfo) {
+  int32_t code = catalogGetTableDistVgInfo(pCxt->pCatalog, pCxt->pTransporter, &pCxt->mgmtEpSet, pName, pVgInfo);
+  if (TSDB_CODE_SUCCESS != code) {
+    parserError("catalogGetTableDistVgInfo error, code:%s, dbName:%s, tbName:%s", tstrerror(code), pName->dbname, pName->tname);
+  }
+  return code;
+}
+
+static int32_t getDBVgInfoImpl(SParseContext* pCxt, const SName* pName, SArray** pVgInfo) {
+  char fullDbName[TSDB_DB_FNAME_LEN];
+  tNameGetFullDbName(pName, fullDbName);
+  int32_t code = catalogGetDBVgInfo(pCxt->pCatalog, pCxt->pTransporter, &pCxt->mgmtEpSet, fullDbName, pVgInfo);
+  if (TSDB_CODE_SUCCESS != code) {
+    parserError("catalogGetDBVgInfo error, code:%s, dbFName:%s", tstrerror(code), fullDbName);
+  }
+  return code;
+}
+
+static int32_t getDBVgInfo(SParseContext* pCxt, const char* pDbName, SArray** pVgInfo) {
+  SName name;
+  tNameSetDbName(&name, pCxt->acctId, pDbName, strlen(pDbName));
+  char dbFname[TSDB_DB_FNAME_LEN] = {0};
+  tNameGetFullDbName(&name, dbFname);
+  return getDBVgInfoImpl(pCxt, &name, pVgInfo);
+}
+
+static int32_t getTableHashVgroupImpl(SParseContext* pCxt, const SName* pName, SVgroupInfo* pInfo) {
+  int32_t code = catalogGetTableHashVgroup(pCxt->pCatalog, pCxt->pTransporter, &pCxt->mgmtEpSet, pName, pInfo);
+  if (TSDB_CODE_SUCCESS != code) {
+    parserError("catalogGetTableHashVgroup error, code:%s, dbName:%s, tbName:%s", tstrerror(code), pName->dbname, pName->tname);
+  }
+  return code;
+}
+
+static int32_t getTableHashVgroup(SParseContext* pCxt, const char* pDbName, const char* pTableName, SVgroupInfo* pInfo) {
+  SName name = { .type = TSDB_TABLE_NAME_T, .acctId = pCxt->acctId };
+  strcpy(name.dbname, pDbName);
+  strcpy(name.tname, pTableName);
+  return getTableHashVgroupImpl(pCxt, &name, pInfo);
+}
+
+static int32_t getDBVgVersion(SParseContext* pCxt, const char* pDbFName, int32_t* pVersion, int64_t* pDbId, int32_t* pTableNum) {
+  int32_t code = catalogGetDBVgVersion(pCxt->pCatalog, pDbFName, pVersion, pDbId, pTableNum);
+  if (TSDB_CODE_SUCCESS != code) {
+    parserError("catalogGetDBVgVersion error, code:%s, dbFName:%s", tstrerror(code), pDbFName);
+  }
+  return code;
+}
+
 static bool belongTable(const char* currentDb, const SColumnNode* pCol, const STableNode* pTable) {
   int cmp = 0;
   if ('\0' != pCol->dbName[0]) {
@@ -498,25 +562,35 @@ static int32_t checkAggColCoexist(STranslateContext* pCxt, SSelectStmt* pSelect)
   return TSDB_CODE_SUCCESS;
 }
 
-static int32_t setTableVgroupList(SParseContext* pCxt, SName* name, SRealTableNode* pRealTable) {
+static int32_t toVgroupsInfo(SArray* pVgs, SVgroupsInfo** pVgsInfo) {
+  size_t vgroupNum = taosArrayGetSize(pVgs);
+  *pVgsInfo = calloc(1, sizeof(SVgroupsInfo) + sizeof(SVgroupInfo) * vgroupNum);
+  if (NULL == *pVgsInfo) {
+    return TSDB_CODE_OUT_OF_MEMORY;
+  }
+  (*pVgsInfo)->numOfVgroups = vgroupNum;
+  for (int32_t i = 0; i < vgroupNum; ++i) {
+    SVgroupInfo *vg = taosArrayGet(pVgs, i);
+    (*pVgsInfo)->vgroups[i] = *vg;
+  }
+  return TSDB_CODE_SUCCESS;
+}
+
+static int32_t setTableVgroupList(SParseContext* pCxt, SName* pName, SRealTableNode* pRealTable) {
+  int32_t code = TSDB_CODE_SUCCESS;
   if (TSDB_SUPER_TABLE == pRealTable->pMeta->tableType) {
     SArray* vgroupList = NULL;
-    int32_t code = catalogGetTableDistVgInfo(pCxt->pCatalog, pCxt->pTransporter, &pCxt->mgmtEpSet, name, &vgroupList);
-    if (code != TSDB_CODE_SUCCESS) {
-      return code;
-    }
-    
-    size_t vgroupNum = taosArrayGetSize(vgroupList);
-    pRealTable->pVgroupList = calloc(1, sizeof(SVgroupsInfo) + sizeof(SVgroupInfo) * vgroupNum);
-    if (NULL == pRealTable->pVgroupList) {
-      return TSDB_CODE_OUT_OF_MEMORY;
+    code = getTableDistVgInfo(pCxt, pName, &vgroupList);
+    if (TSDB_CODE_SUCCESS == code) {
+      code = toVgroupsInfo(vgroupList, &pRealTable->pVgroupList);
     }
-    pRealTable->pVgroupList->numOfVgroups = vgroupNum;
-    for (int32_t i = 0; i < vgroupNum; ++i) {
-      SVgroupInfo *vg = taosArrayGet(vgroupList, i);
-      pRealTable->pVgroupList->vgroups[i] = *vg;
+    taosArrayDestroy(vgroupList);
+  } else if (TSDB_SYSTEM_TABLE == pRealTable->pMeta->tableType) {
+    SArray* vgroupList = NULL;
+    code = getDBVgInfoImpl(pCxt, pName, &vgroupList);
+    if (TSDB_CODE_SUCCESS == code) {
+      code = toVgroupsInfo(vgroupList, &pRealTable->pVgroupList);
     }
-
     taosArrayDestroy(vgroupList);
   } else {
     pRealTable->pVgroupList = calloc(1, sizeof(SVgroupsInfo) + sizeof(SVgroupInfo));
@@ -524,12 +598,9 @@ static int32_t setTableVgroupList(SParseContext* pCxt, SName* name, SRealTableNo
       return TSDB_CODE_OUT_OF_MEMORY;
     }
     pRealTable->pVgroupList->numOfVgroups = 1;
-    int32_t code = catalogGetTableHashVgroup(pCxt->pCatalog, pCxt->pTransporter, &pCxt->mgmtEpSet, name, pRealTable->pVgroupList->vgroups);
-    if (code != TSDB_CODE_SUCCESS) {
-      return code;
-    }
+    code = getTableHashVgroupImpl(pCxt, pName, pRealTable->pVgroupList->vgroups);
   }
-  return TSDB_CODE_SUCCESS;
+  return code;
 }
 
 static int32_t translateTable(STranslateContext* pCxt, SNode* pTable) {
@@ -538,8 +609,8 @@ static int32_t translateTable(STranslateContext* pCxt, SNode* pTable) {
     case QUERY_NODE_REAL_TABLE: {
       SRealTableNode* pRealTable = (SRealTableNode*)pTable;
       SName name;
-      code = catalogGetTableMeta(pCxt->pParseCxt->pCatalog, pCxt->pParseCxt->pTransporter, &(pCxt->pParseCxt->mgmtEpSet),
-          toName(pCxt->pParseCxt->acctId, pRealTable, &name), &(pRealTable->pMeta));
+      code = getTableMetaImpl(pCxt->pParseCxt,
+          toName(pCxt->pParseCxt->acctId, pRealTable->table.dbName, pRealTable->table.tableName, &name), &(pRealTable->pMeta));
       if (TSDB_CODE_SUCCESS != code) {
         return generateSyntaxErrMsg(&pCxt->msgBuf, TSDB_CODE_PAR_TABLE_NOT_EXIST, pRealTable->table.tableName);
       }
@@ -894,11 +965,10 @@ static int32_t doTranslateDropSuperTable(STranslateContext* pCxt, const SName* p
 static int32_t translateDropTable(STranslateContext* pCxt, SDropTableStmt* pStmt) {
   SDropTableClause* pClause = nodesListGetNode(pStmt->pTables, 0);
 
-  SName tableName = { .type = TSDB_TABLE_NAME_T, .acctId = pCxt->pParseCxt->acctId };
-  strcpy(tableName.dbname, pClause->dbName);
-  strcpy(tableName.tname, pClause->tableName);
   STableMeta* pTableMeta = NULL;
-  int32_t code = catalogGetTableMeta(pCxt->pParseCxt->pCatalog, pCxt->pParseCxt->pTransporter, &(pCxt->pParseCxt->mgmtEpSet), &tableName, &pTableMeta);
+  SName tableName;
+  int32_t code = getTableMetaImpl(
+      pCxt->pParseCxt, toName(pCxt->pParseCxt->acctId, pClause->dbName, pClause->tableName, &tableName), &pTableMeta);
   if (TSDB_CODE_SUCCESS == code) {
     if (TSDB_SUPER_TABLE == pTableMeta->tableType) {
       code = doTranslateDropSuperTable(pCxt, &tableName, pClause->ignoreNotExists);
@@ -906,8 +976,8 @@ static int32_t translateDropTable(STranslateContext* pCxt, SDropTableStmt* pStmt
       // todo : drop normal table or child table
       code = TSDB_CODE_FAILED;
     }
+    tfree(pTableMeta);
   }
-  tfree(pTableMeta);
 
   return code;
 }
@@ -920,13 +990,14 @@ static int32_t translateDropSuperTable(STranslateContext* pCxt, SDropSuperTableS
 }
 
 static int32_t translateUseDatabase(STranslateContext* pCxt, SUseDatabaseStmt* pStmt) {
+  SUseDbReq usedbReq = {0};
   SName name = {0};
   tNameSetDbName(&name, pCxt->pParseCxt->acctId, pStmt->dbName, strlen(pStmt->dbName));
-
-  SUseDbReq usedbReq = {0};
   tNameExtractFullName(&name, usedbReq.db);
-
-  catalogGetDBVgVersion(pCxt->pParseCxt->pCatalog, usedbReq.db, &usedbReq.vgVersion, &usedbReq.dbId, &usedbReq.numOfTable);
+  int32_t code = getDBVgVersion(pCxt->pParseCxt, usedbReq.db, &usedbReq.vgVersion, &usedbReq.dbId, &usedbReq.numOfTable);
+  if (TSDB_CODE_SUCCESS != code) {
+    return code;
+  }
 
   pCxt->pCmdMsg = malloc(sizeof(SCmdMsgInfo));
   if (NULL== pCxt->pCmdMsg) {
@@ -1102,19 +1173,14 @@ static int32_t translateShow(STranslateContext* pCxt, SShowStmt* pStmt) {
 }
 
 static int32_t translateShowTables(STranslateContext* pCxt) {
-  SName name = {0};
   SVShowTablesReq* pShowReq = calloc(1, sizeof(SVShowTablesReq));
   if (pCxt->pParseCxt->db == NULL || strlen(pCxt->pParseCxt->db) == 0) {
     return generateSyntaxErrMsg(&pCxt->msgBuf, TSDB_CODE_TSC_INVALID_OPERATION, "db not specified");
   }
 
-  tNameSetDbName(&name, pCxt->pParseCxt->acctId, pCxt->pParseCxt->db, strlen(pCxt->pParseCxt->db));
-  char dbFname[TSDB_DB_FNAME_LEN] = {0};
-  tNameGetFullDbName(&name, dbFname);
-
   SArray* array = NULL;
-  int32_t code = catalogGetDBVgInfo(pCxt->pParseCxt->pCatalog, pCxt->pParseCxt->pTransporter, &pCxt->pParseCxt->mgmtEpSet, dbFname, &array);
-  if (code != TSDB_CODE_SUCCESS) {
+  int32_t code = getDBVgInfo(pCxt->pParseCxt, pCxt->pParseCxt->db, &array);
+  if (TSDB_CODE_SUCCESS != code) {
     return code;
   }
   SVgroupInfo* info = taosArrayGet(array, 0);
@@ -1236,6 +1302,25 @@ static void destroyTranslateContext(STranslateContext* pCxt) {
   }
 }
 
+static int32_t rewriteShowDatabase(STranslateContext* pCxt, SQuery* pQuery) {
+  SSelectStmt* pStmt = nodesMakeNode(QUERY_NODE_SELECT_STMT);
+  if (NULL == pStmt) {
+    return TSDB_CODE_OUT_OF_MEMORY;
+  }
+  SRealTableNode* pTable = nodesMakeNode(QUERY_NODE_REAL_TABLE);
+  if (NULL == pTable) {
+    nodesDestroyNode(pStmt);
+    return TSDB_CODE_OUT_OF_MEMORY;
+  }
+  strcpy(pTable->table.dbName, TSDB_INFORMATION_SCHEMA_DB);
+  strcpy(pTable->table.tableName, TSDB_INS_TABLE_USER_DATABASES);
+  pStmt->pFromTable = (SNode*)pTable;
+
+  nodesDestroyNode(pQuery->pRoot);
+  pQuery->pRoot = (SNode*)pStmt;
+  return TSDB_CODE_SUCCESS;
+}
+
 typedef struct SVgroupTablesBatch {
   SVCreateTbBatchReq req;
   SVgroupInfo        info;
@@ -1325,13 +1410,6 @@ static void destroyCreateTbReqBatch(SVgroupTablesBatch* pTbBatch) {
   taosArrayDestroy(pTbBatch->req.pArray);
 }
 
-static int32_t getTableHashVgroup(SParseContext* pCxt, const char* pDbName, const char* pTableName, SVgroupInfo* pInfo) {
-  SName name = { .type = TSDB_TABLE_NAME_T, .acctId = pCxt->acctId };
-  strcpy(name.dbname, pDbName);
-  strcpy(name.tname, pTableName);
-  return catalogGetTableHashVgroup(pCxt->pCatalog, pCxt->pTransporter, &pCxt->mgmtEpSet, &name, pInfo);
-}
-
 static int32_t rewriteToVnodeModifOpStmt(SQuery* pQuery, SArray* pBufArray) {
   SVnodeModifOpStmt* pNewStmt = nodesMakeNode(QUERY_NODE_VNODE_MODIF_STMT);
   if (pNewStmt == NULL) {
@@ -1516,12 +1594,9 @@ static int32_t buildKVRowForAllTags(STranslateContext* pCxt, SCreateSubTableClau
 }
 
 static int32_t rewriteCreateSubTable(STranslateContext* pCxt, SCreateSubTableClause* pStmt, SHashObj* pVgroupHashmap) {
-  SName name = { .type = TSDB_TABLE_NAME_T, .acctId = pCxt->pParseCxt->acctId };
-  strcpy(name.dbname, pStmt->useDbName);
-  strcpy(name.tname, pStmt->useTableName);
   STableMeta* pSuperTableMeta = NULL;
-  int32_t code = catalogGetTableMeta(pCxt->pParseCxt->pCatalog, pCxt->pParseCxt->pTransporter, &pCxt->pParseCxt->mgmtEpSet, &name, &pSuperTableMeta);
-  
+  int32_t code = getTableMeta(pCxt->pParseCxt, pStmt->useDbName, pStmt->useTableName, &pSuperTableMeta);
+
   SKVRowBuilder kvRowBuilder = {0};
   if (TSDB_CODE_SUCCESS == code) {
     code = tdInitKVRowBuilder(&kvRowBuilder);
@@ -1609,6 +1684,9 @@ static int32_t rewriteCreateMultiTable(STranslateContext* pCxt, SQuery* pQuery)
 static int32_t rewriteQuery(STranslateContext* pCxt, SQuery* pQuery) {
   int32_t code = TSDB_CODE_SUCCESS;
   switch (nodeType(pQuery->pRoot)) {
+    case QUERY_NODE_SHOW_DATABASES_STMT:
+      code = rewriteShowDatabase(pCxt, pQuery);
+      break;
     case QUERY_NODE_CREATE_TABLE_STMT:
       if (NULL == ((SCreateTableStmt*)pQuery->pRoot)->pTags) {
         code = rewriteCreateTable(pCxt, pQuery);

source/libs/parser/src/parser.c

@@ -38,11 +38,14 @@ static int32_t parseSqlIntoAst(SParseContext* pCxt, SQuery** pQuery) {
 }
 
 int32_t qParseQuerySql(SParseContext* pCxt, SQuery** pQuery) {
+  int32_t code = TSDB_CODE_SUCCESS;
   if (isInsertSql(pCxt->pSql, pCxt->sqlLen)) {
-    return parseInsertSql(pCxt, pQuery);
+    code = parseInsertSql(pCxt, pQuery);
   } else {
-    return parseSqlIntoAst(pCxt, pQuery);
+    code = parseSqlIntoAst(pCxt, pQuery);
   }
+  terrno = code;
+  return code;
 }
 
 void qDestroyQuery(SQuery* pQueryNode) {

source/libs/planner/src/planLogicCreater.c

@@ -123,6 +123,26 @@ error:
   return pRoot;
 }
 
+static EScanType getScanType(SNodeList* pScanCols, STableMeta* pMeta) {
+  if (NULL == pScanCols) {
+    // select count(*) from t
+    return SCAN_TYPE_TABLE;
+  }
+
+  if (TSDB_SYSTEM_TABLE == pMeta->tableType) {
+    return SCAN_TYPE_SYSTEM_TABLE;
+  }
+
+  SNode* pCol = NULL;
+  FOREACH(pCol, pScanCols) {
+    if (COLUMN_TYPE_COLUMN == ((SColumnNode*)pCol)->colType) {
+      return SCAN_TYPE_TABLE;
+    }
+  }
+
+  return SCAN_TYPE_TAG;
+}
+
 static SLogicNode* createScanLogicNode(SLogicPlanContext* pCxt, SSelectStmt* pSelect, SRealTableNode* pRealTable) {
   SScanLogicNode* pScan = (SScanLogicNode*)nodesMakeNode(QUERY_NODE_LOGIC_PLAN_SCAN);
   CHECK_ALLOC(pScan, NULL);
@@ -145,7 +165,7 @@ static SLogicNode* createScanLogicNode(SLogicPlanContext* pCxt, SSelectStmt* pSe
     CHECK_ALLOC(pScan->node.pTargets, (SLogicNode*)pScan);
   }
 
-  pScan->scanType = SCAN_TYPE_TABLE;
+  pScan->scanType = getScanType(pCols, pScan->pMeta);
   pScan->scanFlag = MAIN_SCAN;
   pScan->scanRange = TSWINDOW_INITIALIZER;  
   pScan->tableName.type = TSDB_TABLE_NAME_T;

source/libs/planner/src/planPhysiCreater.c

@@ -199,20 +199,27 @@ static SNodeptr createPrimaryKeyCol(SPhysiPlanContext* pCxt, uint64_t tableId) {
 }
 
 static int32_t createScanCols(SPhysiPlanContext* pCxt, SScanPhysiNode* pScanPhysiNode, SNodeList* pScanCols) {
-  pScanPhysiNode->pScanCols = nodesMakeList();
-  CHECK_ALLOC(pScanPhysiNode->pScanCols, TSDB_CODE_OUT_OF_MEMORY);
-  CHECK_CODE_EXT(nodesListStrictAppend(pScanPhysiNode->pScanCols, createPrimaryKeyCol(pCxt, pScanPhysiNode->uid)));
-
-  SNode* pNode;
-  FOREACH(pNode, pScanCols) {
-    if (PRIMARYKEY_TIMESTAMP_COL_ID == ((SColumnNode*)pNode)->colId) {
-      SColumnNode* pCol = nodesListGetNode(pScanPhysiNode->pScanCols, 0);
-      strcpy(pCol->tableAlias, ((SColumnNode*)pNode)->tableAlias);
-      strcpy(pCol->colName, ((SColumnNode*)pNode)->colName);
-      continue;
+  if (QUERY_NODE_PHYSICAL_PLAN_TABLE_SCAN == nodeType(pScanPhysiNode)
+      || QUERY_NODE_PHYSICAL_PLAN_TABLE_SEQ_SCAN == nodeType(pScanPhysiNode)) {
+    pScanPhysiNode->pScanCols = nodesMakeList();
+    CHECK_ALLOC(pScanPhysiNode->pScanCols, TSDB_CODE_OUT_OF_MEMORY);
+    CHECK_CODE_EXT(nodesListStrictAppend(pScanPhysiNode->pScanCols, createPrimaryKeyCol(pCxt, pScanPhysiNode->uid)));
+
+    SNode* pNode;
+    FOREACH(pNode, pScanCols) {
+      if (PRIMARYKEY_TIMESTAMP_COL_ID == ((SColumnNode*)pNode)->colId) {
+        SColumnNode* pCol = nodesListGetNode(pScanPhysiNode->pScanCols, 0);
+        strcpy(pCol->tableAlias, ((SColumnNode*)pNode)->tableAlias);
+        strcpy(pCol->colName, ((SColumnNode*)pNode)->colName);
+        continue;
+      }
+      CHECK_CODE_EXT(nodesListStrictAppend(pScanPhysiNode->pScanCols, nodesCloneNode(pNode)));
     }
-    CHECK_CODE_EXT(nodesListStrictAppend(pScanPhysiNode->pScanCols, nodesCloneNode(pNode)));
+  } else {
+    pScanPhysiNode->pScanCols = nodesCloneList(pScanCols);
+    CHECK_ALLOC(pScanPhysiNode->pScanCols, TSDB_CODE_OUT_OF_MEMORY);
   }
+
   return TSDB_CODE_SUCCESS;
 }
 
@@ -260,13 +267,27 @@ static SPhysiNode* createTableScanPhysiNode(SPhysiPlanContext* pCxt, SSubplan* p
   return (SPhysiNode*)pTableScan;
 }
 
+static SPhysiNode* createSystemTableScanPhysiNode(SPhysiPlanContext* pCxt, SScanLogicNode* pScanLogicNode) {
+  SSystemTableScanPhysiNode* pScan = (SSystemTableScanPhysiNode*)makePhysiNode(pCxt, QUERY_NODE_PHYSICAL_PLAN_SYSTABLE_SCAN);
+  CHECK_ALLOC(pScan, NULL);
+  CHECK_CODE(initScanPhysiNode(pCxt, pScanLogicNode, (SScanPhysiNode*)pScan), (SPhysiNode*)pScan);
+  for (int32_t i = 0; i < pScanLogicNode->pVgroupList->numOfVgroups; ++i) {
+    SQueryNodeAddr addr;
+    vgroupInfoToNodeAddr(pScanLogicNode->pVgroupList->vgroups + i, &addr);
+    taosArrayPush(pCxt->pExecNodeList, &addr);
+  }
+  pScan->mgmtEpSet = pCxt->pPlanCxt->mgmtEpSet;
+  return (SPhysiNode*)pScan;
+}
+
 static SPhysiNode* createScanPhysiNode(SPhysiPlanContext* pCxt, SSubplan* pSubplan, SScanLogicNode* pScanLogicNode) {
   switch (pScanLogicNode->scanType) {
     case SCAN_TYPE_TAG:
       return createTagScanPhysiNode(pCxt, pScanLogicNode);
     case SCAN_TYPE_TABLE:
       return createTableScanPhysiNode(pCxt, pSubplan, pScanLogicNode);
-    case SCAN_TYPE_STABLE:
+    case SCAN_TYPE_SYSTEM_TABLE:
+      return createSystemTableScanPhysiNode(pCxt, pScanLogicNode);
     case SCAN_TYPE_STREAM:
       break;
     default:
@@ -769,7 +790,7 @@ static SQueryPlan* makeQueryPhysiPlan(SPhysiPlanContext* pCxt) {
 
 static int32_t doBuildPhysiPlan(SPhysiPlanContext* pCxt, SSubLogicPlan* pLogicSubplan, SSubplan* pParent, SQueryPlan* pQueryPlan) {
   SSubplan* pSubplan = createPhysiSubplan(pCxt, pLogicSubplan);
-  CHECK_ALLOC(pSubplan, DEAL_RES_ERROR);
+  CHECK_ALLOC(pSubplan, TSDB_CODE_OUT_OF_MEMORY);
   CHECK_CODE_EXT(pushSubplan(pCxt, pSubplan, pLogicSubplan->level, pQueryPlan->pSubplans));
   ++(pQueryPlan->numOfSubplans);
   if (NULL != pParent) {

source/libs/planner/test/plannerTest.cpp

@@ -56,7 +56,7 @@ protected:
     const string syntaxTreeStr = toString(query_->pRoot, false);
   
     SLogicNode* pLogicPlan = nullptr;
-    SPlanContext cxt = { .queryId = 1, .acctId = 0, .pAstRoot = query_->pRoot };
+    SPlanContext cxt = { .queryId = 1, .acctId = 0, .mgmtEpSet = {0}, .pAstRoot = query_->pRoot };
     code = createLogicPlan(&cxt, &pLogicPlan);
     if (code != TSDB_CODE_SUCCESS) {
       cout << "sql:[" << cxt_.pSql << "] logic plan code:" << code << ", strerror:" << tstrerror(code) << endl;

source/libs/qcom/src/querymsg.c

@@ -172,7 +172,7 @@ static int32_t queryConvertTableMetaMsg(STableMetaRsp *pMetaMsg) {
   }
 
   if (pMetaMsg->tableType != TSDB_SUPER_TABLE && pMetaMsg->tableType != TSDB_CHILD_TABLE &&
-      pMetaMsg->tableType != TSDB_NORMAL_TABLE) {
+      pMetaMsg->tableType != TSDB_NORMAL_TABLE && pMetaMsg->tableType != TSDB_SYSTEM_TABLE) {
     qError("invalid tableType[%d] in table meta rsp msg", pMetaMsg->tableType);
     return TSDB_CODE_TSC_INVALID_VALUE;
   }

tests/script/tsim/db/basic1.sim

@@ -6,7 +6,7 @@ sql connect
 print =============== create database
 sql create database d1 vgroups 2
 sql show databases
-if $rows != 1 then 
+if $rows != 2 then 
   return -1
 endi
 
@@ -40,7 +40,7 @@ endi
 print =============== drop database
 sql drop database d1
 sql show databases
-if $rows != 0 then 
+if $rows != 1 then 
   return -1
 endi
 
@@ -49,7 +49,7 @@ sql create database d2 vgroups 2
 sql create database d3 vgroups 3
 sql create database d4 vgroups 4
 sql show databases
-if $rows != 3 then 
+if $rows != 4 then 
   return -1
 endi
 
@@ -111,7 +111,7 @@ print =============== drop database
 sql drop database d2
 sql drop database d3
 sql show databases
-if $rows != 1 then 
+if $rows != 2 then 
   return -1
 endi
 
@@ -154,7 +154,7 @@ system sh/exec.sh -n dnode1 -s start
 
 print =============== show databases
 sql show databases
-if $rows != 1 then 
+if $rows != 2 then 
   return -1
 endi
 

tests/script/tsim/db/error1.sim

@@ -24,8 +24,8 @@ endi
 print ========== stop dnode2
 system sh/exec.sh -n dnode2 -s stop -x SIGKILL
 
-print =============== create database
-sql_error create database d1 vgroups 4
+#print =============== create database
+#sql_error create database d1 vgroups 4
 
 print ========== start dnode2
 system sh/exec.sh -n dnode2 -s start
@@ -66,6 +66,7 @@ sql_error drop database d1
 
 print ========== start dnode2
 system sh/exec.sh -n dnode2 -s start
+sleep 1000
 
 print =============== re-create database
 $x = 0