[td-32] fix bugs in projection query

src/dnode/src/dnodeRead.c

@@ -226,12 +226,26 @@ static void dnodeProcessReadResult(SReadMsg *pRead) {
   rpcFreeCont(pRead->rpcMsg.pCont);  // free the received message
 }
 
+static void dnodeContinueExecuteQuery(void* qhandle, SReadMsg *pMsg) {
+  SReadMsg readMsg = {
+      .rpcMsg      = {.msgType = TSDB_MSG_TYPE_QUERY},
+      .pCont       = qhandle,
+      .contLen     = 0,
+      .pRpcContext = pMsg->pRpcContext,
+      .pVnode      = pMsg->pVnode,
+  };
+  
+  taos_queue queue = dnodeGetVnodeRworker(pMsg->pVnode);
+  taosWriteQitem(queue, &readMsg);
+}
+
 static void dnodeProcessQueryMsg(SReadMsg *pMsg) {
   SQueryTableMsg* pQueryTableMsg = (SQueryTableMsg*) pMsg->pCont;
   
   SQInfo* pQInfo = NULL;
+  if (pMsg->rpcMsg.contLen != 0) {
     void* tsdb = dnodeGetVnodeTsdb(pMsg->pVnode);
-  int32_t code = qCreateQueryInfo(tsdb, pQueryTableMsg, &pQInfo);
+    int32_t code = qCreateQueryInfo(tsdb, pQueryTableMsg, pMsg, &pQInfo);
   
     SQueryTableRsp *pRsp = (SQueryTableRsp *) rpcMallocCont(sizeof(SQueryTableRsp));
     pRsp->code    = code;
@@ -246,27 +260,25 @@ static void dnodeProcessQueryMsg(SReadMsg *pMsg) {
     };
   
     rpcSendResponse(&rpcRsp);
+  } else {
+    pQInfo = pMsg->pCont;
+  }
   
   // do execute query
   qTableQuery(pQInfo);
 }
 
-static int32_t c = 0;
 static void dnodeProcessRetrieveMsg(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);
 
@@ -275,6 +287,10 @@ static void dnodeProcessRetrieveMsg(SReadMsg *pMsg) {
   } else {
     // todo check code and handle error in build result set
     code = qDumpRetrieveResult(pQInfo, &pRsp, &contLen);
+    
+    if (qNeedFurtherExec(pQInfo)) {
+      dnodeContinueExecuteQuery(pQInfo, pMsg);
+    }
   }
   
   SRpcMsg rpcRsp = (SRpcMsg) {

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 {
@@ -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
   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 qNeedFurtherExec(SQInfo* pQInfo);
+
 #endif  // TDENGINE_QUERYEXECUTOR_H

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) {
@@ -367,8 +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 = {