Merge pull request #1422 from taosdata/liaohj_2

Liaohj 2

src/client/src/tscParseInsert.c

@@ -1238,22 +1238,11 @@ int doParseInsertSql(SSqlObj *pSql, char *str) {
     goto _clean;
   }
 
-  // submit to more than one vnode
   if (pCmd->pDataBlocks->nSize > 0) {
     // merge according to vgId
     if ((code = tscMergeTableDataBlocks(pSql, pCmd->pDataBlocks)) != TSDB_CODE_SUCCESS) {
       goto _error_clean;
     }
-
-    STableDataBlocks *pDataBlock = pCmd->pDataBlocks->pData[0];
-    if ((code = tscCopyDataBlockToPayload(pSql, pDataBlock)) != TSDB_CODE_SUCCESS) {
-      goto _error_clean;
-    }
-
-    pTableMetaInfo = tscGetTableMetaInfoFromCmd(&pSql->cmd, 0, 0);
-
-    // set the next sent data vnode index in data block arraylist
-    pTableMetaInfo->vnodeIndex = 1;
   } else {
     pCmd->pDataBlocks = tscDestroyBlockArrayList(pCmd->pDataBlocks);
   }

src/client/src/tscSQLParser.c

@@ -1489,11 +1489,9 @@ static int32_t setExprInfoForFunctions(SQueryInfo* pQueryInfo, SSchema* pSchema,
   SSqlExpr* pExpr = tscSqlExprInsert(pQueryInfo, resColIdx, functionID, pColIndex, type, bytes, bytes);
   strncpy(pExpr->aliasName, columnName, tListLen(pExpr->aliasName));
   
-  // for point interpolation/last_row query, we need the timestamp column to be loaded
+  // for all querie, the timestamp column meeds to be loaded
   SColumnIndex index = {.tableIndex = pColIndex->tableIndex, .columnIndex = PRIMARYKEY_TIMESTAMP_COL_INDEX};
-  if (functionID == TSDB_FUNC_INTERP || functionID == TSDB_FUNC_LAST_ROW) {
-    tscColumnBaseInfoInsert(pQueryInfo, &index);
-  }
+  tscColumnBaseInfoInsert(pQueryInfo, &index);
 
   SColumnList ids = getColumnList(1, pColIndex->tableIndex, pColIndex->columnIndex);
   insertResultField(pQueryInfo, resColIdx, &ids, bytes, type, columnName, pExpr);
@@ -1581,7 +1579,10 @@ int32_t addExprAndResultField(SQueryInfo* pQueryInfo, int32_t colIdx, tSQLExprIt
           tscColumnBaseInfoInsert(pQueryInfo, &(ids.ids[i]));
         }
       }
-      
+  
+      SColumnIndex tsCol = {.tableIndex = index.tableIndex, .columnIndex = PRIMARYKEY_TIMESTAMP_COL_INDEX};
+      tscColumnBaseInfoInsert(pQueryInfo, &tsCol);
+  
       return TSDB_CODE_SUCCESS;
     }
     case TK_SUM:
@@ -1689,7 +1690,10 @@ int32_t addExprAndResultField(SQueryInfo* pQueryInfo, int32_t colIdx, tSQLExprIt
           tscColumnBaseInfoInsert(pQueryInfo, &(ids.ids[i]));
         }
       }
-
+  
+      SColumnIndex tsCol = {.tableIndex = index.tableIndex, .columnIndex = PRIMARYKEY_TIMESTAMP_COL_INDEX};
+      tscColumnBaseInfoInsert(pQueryInfo, &tsCol);
+      
       return TSDB_CODE_SUCCESS;
     }
     case TK_FIRST:
@@ -1708,7 +1712,6 @@ int32_t addExprAndResultField(SQueryInfo* pQueryInfo, int32_t colIdx, tSQLExprIt
         }
 
         /* in first/last function, multiple columns can be add to resultset */
-
         for (int32_t i = 0; i < pItem->pNode->pParam->nExpr; ++i) {
           tSQLExprItem* pParamElem = &(pItem->pNode->pParam->a[i]);
           if (pParamElem->pNode->nSQLOptr != TK_ALL && pParamElem->pNode->nSQLOptr != TK_ID) {
@@ -1753,7 +1756,7 @@ int32_t addExprAndResultField(SQueryInfo* pQueryInfo, int32_t colIdx, tSQLExprIt
             }
           }
         }
-
+        
         return TSDB_CODE_SUCCESS;
       } else {  // select * from xxx
         int32_t numOfFields = 0;
@@ -1773,6 +1776,7 @@ int32_t addExprAndResultField(SQueryInfo* pQueryInfo, int32_t colIdx, tSQLExprIt
           numOfFields += tscGetNumOfColumns(pTableMetaInfo->pTableMeta);
         }
 
+        
         return TSDB_CODE_SUCCESS;
       }
     }
@@ -1891,6 +1895,8 @@ int32_t addExprAndResultField(SQueryInfo* pQueryInfo, int32_t colIdx, tSQLExprIt
     default:
       return TSDB_CODE_INVALID_SQL;
   }
+  
+  
 }
 
 // todo refactor

src/client/src/tscServer.c

@@ -341,14 +341,8 @@ void tscProcessMsgFromServer(SRpcMsg *rpcMsg) {
     (*pSql->fp)(pSql->param, taosres, rpcMsg->code);
 
     if (shouldFree) {
-      // If it is failed, all objects allocated during execution taos_connect_a should be released
-      if (command == TSDB_SQL_CONNECT) {
-        taos_close(pObj);
-        tscTrace("%p Async sql close failed connection", pSql);
-      } else {
-        tscFreeSqlObj(pSql);
-        tscTrace("%p Async sql is automatically freed", pSql);
-      }
+      tscFreeSqlObj(pSql);
+      tscTrace("%p Async sql is automatically freed", pSql);
     }
   }
 

src/client/src/tscSql.c

@@ -594,11 +594,7 @@ static void **tscBuildResFromSubqueries(SSqlObj *pSql) {
     }
 
     if (numOfTableHasRes >= 2) {  // do merge result
-
       success = (doSetResultRowData(pSql->pSubs[0]) != NULL) && (doSetResultRowData(pSql->pSubs[1]) != NULL);
-      //        TSKEY key1 = *(TSKEY *)pRes1->tsrow[0];
-      //        TSKEY key2 = *(TSKEY *)pRes2->tsrow[0];
-      //        printf("first:%" PRId64 ", second:%" PRId64 "\n", key1, key2);
     } else {  // only one subquery
       SSqlObj *pSub = pSql->pSubs[0];
       if (pSub == NULL) {
@@ -674,14 +670,13 @@ TAOS_ROW taos_fetch_row(TAOS_RES *res) {
   SSqlRes *pRes = &pSql->res;
   
   if (pRes->qhandle == 0 ||
-      pRes->completed ||
       pCmd->command == TSDB_SQL_RETRIEVE_EMPTY_RESULT ||
       pCmd->command == TSDB_SQL_INSERT) {
     return NULL;
   }
   
   // current data are exhausted, fetch more data
-  if (pRes->data == NULL || (pRes->data != NULL && pRes->row >= pRes->numOfRows &&
+  if (pRes->data == NULL || (pRes->data != NULL && pRes->row >= pRes->numOfRows && pRes->completed != true &&
       (pCmd->command == TSDB_SQL_RETRIEVE || pCmd->command == TSDB_SQL_RETRIEVE_METRIC || pCmd->command == TSDB_SQL_FETCH))) {
     taos_fetch_rows_a(res, asyncFetchCallback, pSql->pTscObj);
     

src/client/src/tscStream.c

@@ -504,7 +504,6 @@ TAOS_STREAM *taos_open_stream(TAOS *taos, const char *sqlstr, void (*fp)(void *p
   }
 
   tsem_init(&pSql->rspSem, 0, 0);
-  tsem_init(&pSql->emptyRspSem, 0, 1);
 
   SSqlInfo SQLInfo = {0};
   tSQLParse(&SQLInfo, pSql->sqlstr);

src/client/src/tscUtil.c

@@ -423,9 +423,6 @@ void tscFreeResData(SSqlObj* pSql) {
 }
 
 void tscFreeSqlResult(SSqlObj* pSql) {
-  //TODO not free
-  return;
-
   tfree(pSql->res.pRsp);
   pSql->res.row = 0;
   pSql->res.numOfRows = 0;
@@ -469,8 +466,6 @@ void tscFreeSqlObjPartial(SSqlObj* pSql) {
   tscFreeSqlCmdData(pCmd);
   
   tscTrace("%p free sqlObj partial completed", pSql);
-  
-  tscFreeSqlCmdData(pCmd);
 }
 
 void tscFreeSqlObj(SSqlObj* pSql) {
@@ -489,10 +484,7 @@ void tscFreeSqlObj(SSqlObj* pSql) {
 
   pCmd->allocSize = 0;
 
-  if (pSql->fp == NULL) {
-    tsem_destroy(&pSql->rspSem);
-    tsem_destroy(&pSql->emptyRspSem);
-  }
+  tsem_destroy(&pSql->rspSem);
   free(pSql);
 }
 
@@ -721,7 +713,7 @@ static void trimDataBlock(void* pDataBlock, STableDataBlocks* pTableDataBlock) {
   
   char* p = pTableDataBlock->pData + sizeof(SSubmitBlk);
   
-  SSubmitBlk* pBlock = pTableDataBlock->pData;
+  SSubmitBlk* pBlock = (SSubmitBlk*) pTableDataBlock->pData;
   int32_t rows = htons(pBlock->numOfRows);
   
   for(int32_t i = 0; i < rows; ++i) {
@@ -1751,16 +1743,8 @@ bool tscShouldFreeAsyncSqlObj(SSqlObj* pSql) {
   }
 
   int32_t command = pSql->cmd.command;
-  if (pTscObj->pSql == pSql) {
-    /*
-     * in case of taos_connect_a query, the object should all be released, even it is the
-     * master sql object. Otherwise, the master sql should not be released
-     */
-    if (command == TSDB_SQL_CONNECT && pSql->res.code != TSDB_CODE_SUCCESS) {
-      return true;
-    }
-
-    return false;
+  if (command == TSDB_SQL_CONNECT) {
+    return true;
   }
 
   if (command == TSDB_SQL_INSERT) {

src/dnode/src/dnodeRead.c

@@ -176,10 +176,10 @@ static void *dnodeProcessReadQueue(void *param) {
       terrno = TSDB_CODE_MSG_NOT_PROCESSED;
     }
 
-    dnodeProcessReadResult(pVnode, pReadMsg);
+//    dnodeProcessReadResult(pVnode, pReadMsg);
     taosFreeQitem(pReadMsg);
 
-    dnodeReleaseVnode(pVnode);  
+    dnodeReleaseVnode(pVnode);
   }
 
   return NULL;
@@ -220,7 +220,7 @@ static void dnodeProcessReadResult(void *pVnode, SReadMsg *pRead) {
     code = terrno;
   }
 
-  //TODO: query handle is returned by dnodeProcessQueryMsg 
+  //TODO: query handle is returned by dnodeProcessQueryMsg
   if (0) {
     SRpcMsg rsp;
     rsp.handle = pRead->rpcMsg.handle;
@@ -232,47 +232,67 @@ static void dnodeProcessReadResult(void *pVnode, SReadMsg *pRead) {
   rpcFreeCont(pRead->rpcMsg.pCont);  // free the received message
 }
 
+static void dnodeContinueExecuteQuery(void* pVnode, void* qhandle, SReadMsg *pMsg) {
+  
+  SReadMsg *pRead = (SReadMsg *)taosAllocateQitem(sizeof(SReadMsg));
+  pRead->rpcMsg      = pMsg->rpcMsg;
+  pRead->pCont       = qhandle;
+  pRead->contLen     = 0;
+  pRead->pRpcContext = pMsg->pRpcContext;
+  pRead->rpcMsg.msgType = TSDB_MSG_TYPE_QUERY;
+  
+  taos_queue queue = dnodeGetVnodeRworker(pVnode);
+  taosWriteQitem(queue, TAOS_QTYPE_RPC, pRead);
+  
+//  SReadMsg readMsg = {
+//      .rpcMsg      = {0},
+//      .pCont       = qhandle,
+//      .contLen     = 0,
+//      .pRpcContext = pMsg->pRpcContext,
+//  };
+//
+//  taos_queue queue = dnodeGetVnodeRworker(pVnode);
+//  taosWriteQitem(queue, TSDB_MSG_TYPE_QUERY, &readMsg);
+}
+
 static void dnodeProcessQueryMsg(void *pVnode, SReadMsg *pMsg) {
   SQueryTableMsg* pQueryTableMsg = (SQueryTableMsg*) pMsg->pCont;
   
   SQInfo* pQInfo = NULL;
-  void* tsdb = dnodeGetVnodeTsdb(pVnode);
-  int32_t code = qCreateQueryInfo(tsdb, pQueryTableMsg, &pQInfo);
+  if (pMsg->contLen != 0) {
+    void* tsdb = dnodeGetVnodeTsdb(pVnode);
+    int32_t code = qCreateQueryInfo(tsdb, pQueryTableMsg, NULL, &pQInfo);
   
-  SQueryTableRsp *pRsp = (SQueryTableRsp *) rpcMallocCont(sizeof(SQueryTableRsp));
-  pRsp->code    = code;
-  pRsp->qhandle = htobe64((uint64_t) (pQInfo));
-
-  SRpcMsg rpcRsp = {
-      .handle = pMsg->rpcMsg.handle,
-      .pCont = pRsp,
-      .contLen = sizeof(SQueryTableRsp),
-      .code = code,
-      .msgType = 0
-  };
+    SQueryTableRsp *pRsp = (SQueryTableRsp *) rpcMallocCont(sizeof(SQueryTableRsp));
+    pRsp->code    = code;
+    pRsp->qhandle = htobe64((uint64_t) (pQInfo));
   
-  rpcSendResponse(&rpcRsp);
+    SRpcMsg rpcRsp = {
+        .handle = pMsg->rpcMsg.handle,
+        .pCont = pRsp,
+        .contLen = sizeof(SQueryTableRsp),
+        .code = code,
+        .msgType = 0
+    };
   
-  // do execute query
-  qTableQuery(pQInfo);
+    rpcSendResponse(&rpcRsp);
+  } else {
+    pQInfo = pMsg->pCont;
+  }
+  
+  qTableQuery(pQInfo); // do execute query
 }
 
-static int32_t c = 0;
 static void dnodeProcessRetrieveMsg(void *pVnode, SReadMsg *pMsg) {
   SRetrieveTableMsg *pRetrieve = pMsg->pCont;
   void *pQInfo = (void*) htobe64(pRetrieve->qhandle);
 
   dTrace("QInfo:%p vgId:%d, retrieve msg is received", pQInfo, pRetrieve->header.vgId);
-  if ((++c)%2 == 0) {
-    int32_t k = 1;
-  }
-  int32_t rowSize = 0;
-  int32_t numOfRows = 0;
   int32_t contLen = 0;
   
   SRetrieveTableRsp *pRsp = NULL;
   
-  int32_t code = qRetrieveQueryResultInfo(pQInfo, &numOfRows, &rowSize);
+  int32_t code = qRetrieveQueryResultInfo(pQInfo);
   if (code != TSDB_CODE_SUCCESS) {
     contLen = sizeof(SRetrieveTableRsp);
 
@@ -281,6 +301,12 @@ static void dnodeProcessRetrieveMsg(void *pVnode, SReadMsg *pMsg) {
   } else {
     // todo check code and handle error in build result set
     code = qDumpRetrieveResult(pQInfo, &pRsp, &contLen);
+    
+    if (qHasMoreResultsToRetrieve(pQInfo)) {
+      dnodeContinueExecuteQuery(pVnode, pQInfo, pMsg);
+    } else {  // no further execution invoked, release the ref to vnode
+      dnodeProcessReadResult(pVnode, pMsg);
+    }
   }
   
   SRpcMsg rpcRsp = (SRpcMsg) {
@@ -292,7 +318,4 @@ static void dnodeProcessRetrieveMsg(void *pVnode, SReadMsg *pMsg) {
   };
 
   rpcSendResponse(&rpcRsp);
-  
-  //todo merge result should be done here
-  //dnodeProcessReadResult(&readMsg);
 }

src/query/inc/queryExecutor.h

@@ -68,8 +68,10 @@ typedef struct SWindowResult {
 } SWindowResult;
 
 typedef struct SResultRec {
-  int64_t pointsTotal;
-  int64_t pointsRead;
+  int64_t total;
+  int64_t size;
+  int64_t capacity;
+  int32_t threshold;   // the threshold size, when the number of rows in result buffer, return to client
 } SResultRec;
 
 typedef struct SWindowResInfo {
@@ -112,7 +114,7 @@ typedef struct STableQueryInfo {
 
 typedef struct STableDataInfo {
   int32_t          numOfBlocks;
-  int32_t          start;  // start block index
+  int32_t          start;     // start block index
   int32_t          tableIndex;
   void*            pMeterObj;
   int32_t          groupIdx;  // group id in table list
@@ -143,7 +145,6 @@ typedef struct SQuery {
   int32_t           pos;
   int64_t           pointsOffset;  // the number of points offset to save read data
   SData**           sdata;
-  int32_t           capacity;
   SSingleColumnFilterInfo* pFilterInfo;
 } SQuery;
 
@@ -171,15 +172,13 @@ typedef struct SQueryRuntimeEnv {
 
 typedef struct SQInfo {
   void*            signature;
-  void*            pVnode;
+//  void*            param;         // pointer to the RpcReadMsg
   TSKEY            startTime;
   TSKEY            elapsedTime;
-  SResultRec       rec;
   int32_t          pointsInterpo;
-  int32_t          code;   // error code to returned to client
-//  int32_t          killed; // denotes if current query is killed
+  int32_t          code;          // error code to returned to client
   sem_t            dataReady;
-  SArray*          pTableIdList;  // table list
+  SArray*          pTableIdList;  // table id list
   SQueryRuntimeEnv runtimeEnv;
   int32_t          subgroupIdx;
   int32_t          offset; /* offset in group result set of subgroup */
@@ -204,7 +203,7 @@ typedef struct SQInfo {
  * @param pQInfo
  * @return
  */
-int32_t qCreateQueryInfo(void* pVnode, SQueryTableMsg* pQueryTableMsg, SQInfo** pQInfo);
+int32_t qCreateQueryInfo(void* pVnode, SQueryTableMsg* pQueryTableMsg, void* param, SQInfo** pQInfo);
 
 /**
  * query on single table
@@ -222,7 +221,7 @@ void qSuperTableQuery(void* pReadMsg);
  * wait for the query completed, and retrieve final results to client
  * @param pQInfo
  */
-int32_t qRetrieveQueryResultInfo(SQInfo* pQInfo, int32_t *numOfRows, int32_t* rowsize);
+int32_t qRetrieveQueryResultInfo(SQInfo* pQInfo);
 
 /**
  *
@@ -232,4 +231,11 @@ int32_t qRetrieveQueryResultInfo(SQInfo* pQInfo, int32_t *numOfRows, int32_t* ro
  */
 int32_t qDumpRetrieveResult(SQInfo *pQInfo, SRetrieveTableRsp** pRsp, int32_t* contLen);
 
+/**
+ *
+ * @param pQInfo
+ * @return
+ */
+bool qHasMoreResultsToRetrieve(SQInfo* pQInfo);
+
 #endif  // TDENGINE_QUERYEXECUTOR_H

src/rpc/src/rpcMain.c

@@ -32,6 +32,7 @@
 #include "rpcServer.h"
 #include "rpcHead.h"
 #include "trpc.h"
+#include "hash.h"
 
 #define RPC_MSG_OVERHEAD (sizeof(SRpcReqContext) + sizeof(SRpcHead) + sizeof(SRpcDigest)) 
 #define rpcHeadFromCont(cont) ((SRpcHead *) (cont - sizeof(SRpcHead)))
@@ -258,7 +259,8 @@ void *rpcOpen(SRpcInit *pInit) {
   }
 
   if (pRpc->connType == TAOS_CONN_SERVER) {
-    pRpc->hash = taosInitStrHash(pRpc->sessions, sizeof(pRpc), taosHashString);
+//    pRpc->hash = taosInitStrHash(pRpc->sessions, sizeof(pRpc), taosHashString);
+      pRpc->hash = taosHashInit(pRpc->sessions, taosGetDefaultHashFunction(TSDB_DATA_TYPE_BINARY), true);
     if (pRpc->hash == NULL) {
       tError("%s failed to init string hash", pRpc->label);
       rpcClose(pRpc);
@@ -292,7 +294,8 @@ void rpcClose(void *param) {
     }
   }
 
-  taosCleanUpStrHash(pRpc->hash);
+//  taosCleanUpStrHash(pRpc->hash);
+  taosHashCleanup(pRpc->hash);
   taosTmrCleanUp(pRpc->tmrCtrl);
   taosIdPoolCleanUp(pRpc->idPool);
   rpcCloseConnCache(pRpc->pCache);
@@ -507,8 +510,10 @@ static void rpcCloseConn(void *thandle) {
 
   if ( pRpc->connType == TAOS_CONN_SERVER) {
     char hashstr[40] = {0};
-    sprintf(hashstr, "%x:%x:%x:%d", pConn->peerIp, pConn->linkUid, pConn->peerId, pConn->connType);
-    taosDeleteStrHash(pRpc->hash, hashstr);
+    size_t size = sprintf(hashstr, "%x:%x:%x:%d", pConn->peerIp, pConn->linkUid, pConn->peerId, pConn->connType);
+//    taosDeleteStrHash(pRpc->hash, hashstr);
+//    taosHashRemove(pRpc->hash, hashstr, size);
+    
     rpcFreeMsg(pConn->pRspMsg); // it may have a response msg saved, but not request msg
     pConn->pRspMsg = NULL;
     pConn->inType = 0;
@@ -556,10 +561,11 @@ static SRpcConn *rpcAllocateServerConn(SRpcInfo *pRpc, SRecvInfo *pRecv) {
   char      hashstr[40] = {0};
   SRpcHead *pHead = (SRpcHead *)pRecv->msg;
 
-  sprintf(hashstr, "%x:%x:%x:%d", pRecv->ip, pHead->linkUid, pHead->sourceId, pRecv->connType);
+  size_t size = sprintf(hashstr, "%x:%x:%x:%d", pRecv->ip, pHead->linkUid, pHead->sourceId, pRecv->connType);
  
   // check if it is already allocated
-  SRpcConn **ppConn = (SRpcConn **)(taosGetStrHashData(pRpc->hash, hashstr));
+//  SRpcConn **ppConn = (SRpcConn **)(taosGetStrHashData(pRpc->hash, hashstr));
+  SRpcConn **ppConn = (SRpcConn **)(taosHashGet(pRpc->hash, hashstr, size));
   if (ppConn) pConn = *ppConn;
   if (pConn) return pConn;
 
@@ -591,7 +597,9 @@ static SRpcConn *rpcAllocateServerConn(SRpcInfo *pRpc, SRecvInfo *pRecv) {
       pConn->localPort = (pRpc->localPort + pRpc->index);
     }
 
-    taosAddStrHash(pRpc->hash, hashstr, (char *)&pConn);
+//    taosAddStrHash(pRpc->hash, hashstr, (char *)&pConn);
+    taosHashPut(pRpc->hash, hashstr, size, (char *)&pConn, POINTER_BYTES);
+    
     tTrace("%s %p, rpc connection is allocated, sid:%d id:%s port:%u", 
            pRpc->label, pConn, sid, pConn->user, pConn->localPort);
   }

src/vnode/detail/src/vnodeQueryImpl.c

@@ -5312,7 +5312,7 @@ static int64_t doScanAllDataBlocks(SQueryRuntimeEnv *pRuntimeEnv) {
 
   while (1) {
     // check if query is killed or not set the status of query to pass the status check
-    if (isQueryKilled(pQuery)) {
+    if (isQueryKilled(pQInfo)) {
       setQueryStatus(pQuery, QUERY_NO_DATA_TO_CHECK);
       return cnt;
     }
@@ -6375,7 +6375,7 @@ void vnodeScanAllData(SQueryRuntimeEnv *pRuntimeEnv) {
     pRuntimeEnv->scanFlag = REPEAT_SCAN;
 
     /* check if query is killed or not */
-    if (isQueryKilled(pQuery)) {
+    if (isQueryKilled(pQInfo)) {
       setQueryStatus(pQuery, QUERY_NO_DATA_TO_CHECK);
       return;
     }

src/vnode/detail/src/vnodeQueryProcess.c

@@ -105,7 +105,7 @@ static void queryOnMultiDataCache(SQInfo *pQInfo, SMeterDataInfo *pMeterDataInfo
     int32_t start = pSupporter->pSidSet->starterPos[groupIdx];
     int32_t end = pSupporter->pSidSet->starterPos[groupIdx + 1] - 1;
 
-    if (isQueryKilled(pQuery)) {
+    if (isQueryKilled(pQInfo)) {
       return;
     }
 
@@ -276,7 +276,7 @@ static void queryOnMultiDataFiles(SQInfo *pQInfo, SMeterDataInfo *pMeterDataInfo
   int64_t st = taosGetTimestampUs();
 
   while (1) {
-    if (isQueryKilled(pQuery)) {
+    if (isQueryKilled(pQInfo)) {
       break;
     }
 
@@ -363,7 +363,7 @@ static void queryOnMultiDataFiles(SQInfo *pQInfo, SMeterDataInfo *pMeterDataInfo
     int32_t j = QUERY_IS_ASC_QUERY(pQuery) ? 0 : numOfBlocks - 1;
 
     for (; j < numOfBlocks && j >= 0; j += step) {
-      if (isQueryKilled(pQuery)) {
+      if (isQueryKilled(pQInfo)) {
         break;
       }
 
@@ -603,7 +603,7 @@ static void vnodeSTableSeqProcessor(SQInfo *pQInfo) {
         pSupporter->meterIdx = start;
 
         for (int32_t k = start; k <= end; ++k, pSupporter->meterIdx++) {
-          if (isQueryKilled(pQuery)) {
+          if (isQueryKilled(pQInfo)) {
             setQueryStatus(pQuery, QUERY_NO_DATA_TO_CHECK);
             return;
           }
@@ -630,7 +630,7 @@ static void vnodeSTableSeqProcessor(SQInfo *pQInfo) {
                pSupporter->subgroupIdx);
 
         for (int32_t k = start; k <= end; ++k) {
-          if (isQueryKilled(pQuery)) {
+          if (isQueryKilled(pQInfo)) {
             setQueryStatus(pQuery, QUERY_NO_DATA_TO_CHECK);
             return;
           }
@@ -681,7 +681,7 @@ static void vnodeSTableSeqProcessor(SQInfo *pQInfo) {
     while (pSupporter->meterIdx < pSupporter->numOfMeters) {
       int32_t k = pSupporter->meterIdx;
 
-      if (isQueryKilled(pQuery)) {
+      if (isQueryKilled(pQInfo)) {
         setQueryStatus(pQuery, QUERY_NO_DATA_TO_CHECK);
         return;
       }
@@ -958,7 +958,7 @@ static void vnodeMultiMeterQueryProcessor(SQInfo *pQInfo) {
 
   doMultiMeterSupplementaryScan(pQInfo);
 
-  if (isQueryKilled(pQuery)) {
+  if (isQueryKilled(pQInfo)) {
     dTrace("QInfo:%p query killed, abort", pQInfo);
     return;
   }
@@ -998,7 +998,7 @@ static void vnodeSingleTableFixedOutputProcessor(SQInfo *pQInfo) {
   vnodeScanAllData(pRuntimeEnv);
   doFinalizeResult(pRuntimeEnv);
 
-  if (isQueryKilled(pQuery)) {
+  if (isQueryKilled(pQInfo)) {
     return;
   }
 
@@ -1033,7 +1033,7 @@ static void vnodeSingleTableMultiOutputProcessor(SQInfo *pQInfo) {
     vnodeScanAllData(pRuntimeEnv);
     doFinalizeResult(pRuntimeEnv);
 
-    if (isQueryKilled(pQuery)) {
+    if (isQueryKilled(pQInfo)) {
       return;
     }
 
@@ -1087,7 +1087,7 @@ static void vnodeSingleMeterIntervalMainLooper(STableQuerySupportObj *pSupporter
     initCtxOutputBuf(pRuntimeEnv);
     vnodeScanAllData(pRuntimeEnv);
     
-    if (isQueryKilled(pQuery)) {
+    if (isQueryKilled(pQInfo)) {
       return;
     }
 
@@ -1301,7 +1301,7 @@ void vnodeSingleTableQuery(SSchedMsg *pMsg) {
   pQInfo->useconds += (taosGetTimestampUs() - st);
 
   /* check if query is killed or not */
-  if (isQueryKilled(pQuery)) {
+  if (isQueryKilled(pQInfo)) {
     dTrace("QInfo:%p query is killed", pQInfo);
     pQInfo->over = 1;
   } else {
@@ -1345,7 +1345,7 @@ void vnodeMultiMeterQuery(SSchedMsg *pMsg) {
 
   /* record the total elapsed time */
   pQInfo->useconds += (taosGetTimestampUs() - st);
-  pQInfo->over = isQueryKilled(pQuery) ? 1 : 0;
+  pQInfo->over = isQueryKilled(pQInfo) ? 1 : 0;
 
   taosInterpoSetStartInfo(&pQInfo->pTableQuerySupporter->runtimeEnv.interpoInfo, pQuery->pointsRead,
                           pQInfo->query.interpoType);

src/vnode/tsdb/src/tsdbRead.c

@@ -124,6 +124,7 @@ typedef struct STsdbQueryHandle {
   int32_t                tableIndex;
   bool                   isFirstSlot;
   void *                 qinfo;  // query info handle, for debug purpose
+  SSkipListIterator*     memIter;
 } STsdbQueryHandle;
 
 int32_t doAllocateBuf(STsdbQueryHandle *pQueryHandle, int32_t rowsPerFileBlock) {
@@ -335,7 +336,6 @@ static int tsdbReadRowsFromCache(SSkipListIterator *pIter, TSKEY maxKey, int max
     
     SDataRow row = SL_GET_NODE_DATA(node);
     if (dataRowKey(row) > maxKey) break;
-    // Convert row data to column data
     
     if (*skey == INT64_MIN) {
       *skey = dataRowKey(row);
@@ -345,13 +345,13 @@ static int tsdbReadRowsFromCache(SSkipListIterator *pIter, TSKEY maxKey, int max
     
     int32_t offset = 0;
     for(int32_t i = 0; i < numOfCols; ++i) {
-      SColumnInfoEx* pColInfo = taosArrayGet(pHandle->pColumns, 0);
+      SColumnInfoEx* pColInfo = taosArrayGet(pHandle->pColumns, i);
       memcpy(pColInfo->pData + numOfRows*pColInfo->info.bytes, dataRowTuple(row) + offset, pColInfo->info.bytes);
       offset += pColInfo->info.bytes;
     }
     
     numOfRows++;
-    if (numOfRows > maxRowsToRead) break;
+    if (numOfRows >= maxRowsToRead) break;
   };
   
   return numOfRows;
@@ -368,8 +368,13 @@ SDataBlockInfo tsdbRetrieveDataBlockInfo(tsdb_query_handle_t *pQueryHandle) {
   int32_t rows = 0;
   
   if (pTable->mem != NULL) {
-    SSkipListIterator* iter = tSkipListCreateIter(pTable->mem->pData);
-    rows = tsdbReadRowsFromCache(iter, INT64_MAX, 4000, &skey, &ekey, pHandle);
+    
+    // create mem table iterator if it is not created yet
+    if (pHandle->memIter == NULL) {
+      pHandle->memIter = tSkipListCreateIter(pTable->mem->pData);
+    }
+    
+    rows = tsdbReadRowsFromCache(pHandle->memIter, INT64_MAX, 2, &skey, &ekey, pHandle);
   }
   
   SDataBlockInfo blockInfo = {
@@ -392,7 +397,9 @@ int32_t tsdbRetrieveDataBlockStatisInfo(tsdb_query_handle_t *pQueryHandle, SData
 }
 
 SArray *tsdbRetrieveDataBlock(tsdb_query_handle_t *pQueryHandle, SArray *pIdList) {
-
+  // in case of data in cache, all data has been kept in column info object.
+  STsdbQueryHandle* pHandle = (STsdbQueryHandle*) pQueryHandle;
+  return pHandle->pColumns;
 }
 
 int32_t tsdbResetQuery(tsdb_query_handle_t *pQueryHandle, STimeWindow *window, tsdbpos_t position, int16_t order) {}

tests/examples/c/demo.c

@@ -64,6 +64,9 @@ int main(int argc, char *argv[]) {
     memset(buf, 0, 512);
   }
   
+  taos_close(taos);
+  
+  getchar();
   return 0;
   
   taos_query(taos, "drop database demo");