[td-2859]<feature>: support nest query.

src/client/inc/tsclient.h

@@ -230,7 +230,8 @@ typedef struct SQueryInfo {
   char*            buf;
 
   struct SQueryInfo *sibling;     // sibling
-  SArray            *pUpstream;   //SArray<struct SQueryInfo>
+  SArray            *pUpstream;   // SArray<struct SQueryInfo>
+  SArray            *pDownstream; // SArray<struct SQueryInfo>
 } SQueryInfo;
 
 typedef struct {

src/client/src/tscSQLParser.c

@@ -6677,8 +6677,11 @@ int32_t validateSqlNode(SSqlObj* pSql, SQuerySqlNode* pQuerySqlNode, int32_t ind
     tscInitQueryInfo(pQueryInfo1);
 
     pQueryInfo1->pUpstream = taosArrayInit(4, POINTER_BYTES);
+    pQueryInfo1->pDownstream = taosArrayInit(4, POINTER_BYTES);
+
     for(int32_t x = 0; x < pCmd->numOfClause; ++x) {
       taosArrayPush(pQueryInfo1->pUpstream, &pCmd->pQueryInfo[x]);
+      taosArrayPush(pCmd->pQueryInfo[x]->pDownstream, &pQueryInfo1);
     }
 
     pQueryInfo1->numOfTables = 1;

src/client/src/tscServer.c

@@ -2331,6 +2331,7 @@ int tscProcessRetrieveRspFromNode(SSqlObj *pSql) {
   }
 
   prepareInputDataFromUpstream(pRes, pQueryInfo);
+
   if (pSql->pSubscription != NULL) {
     int32_t numOfCols = pQueryInfo->fieldsInfo.numOfOutput;
     

src/client/src/tscUtil.c

@@ -372,7 +372,11 @@ void tscSetResRawPtr(SSqlRes* pRes, SQueryInfo* pQueryInfo) {
 }
 
 void prepareInputDataFromUpstream(SSqlRes* pRes, SQueryInfo* pQueryInfo) {
-  printf("abc\n");
+  if (pQueryInfo->pDownstream != NULL && taosArrayGetSize(pQueryInfo->pDownstream) > 0) {
+    // handle the following query process
+    SQueryInfo* px = taosArrayGetP(pQueryInfo->pDownstream, 0);
+    printf("%d\n", px->type);
+  }
 }
 
 static void tscDestroyResPointerInfo(SSqlRes* pRes) {
@@ -1772,6 +1776,8 @@ void tscInitQueryInfo(SQueryInfo* pQueryInfo) {
   pQueryInfo->slimit.limit   = -1;
   pQueryInfo->slimit.offset  = 0;
   pQueryInfo->pUpstream      = taosArrayInit(4, POINTER_BYTES);
+  pQueryInfo->pDownstream    = taosArrayInit(4, POINTER_BYTES);
+
 }
 
 int32_t tscAddQueryInfo(SSqlCmd* pCmd) {

src/query/src/qExecutor.c

@@ -5770,7 +5770,7 @@ _cleanup:
   return code;
 }
 
-static int32_t buildArithmeticExprFromMsg(SExprInfo *pArithExprInfo, SQueryTableMsg *pQueryMsg) {
+static int32_t buildArithmeticExprFromMsg(SExprInfo *pArithExprInfo, void *pQueryMsg) {
   qDebug("qmsg:%p create arithmetic expr from binary", pQueryMsg);
 
   tExprNode* pExprNode = NULL;
@@ -5812,17 +5812,25 @@ static int32_t updateOutputBufForTopBotQuery(SQueryTableMsg* pQueryMsg, SColumnI
 }
 
 // TODO tag length should be passed from client
+typedef struct {
+  int32_t numOfOutput;
+  int32_t numOfTags;
+  int32_t numOfCols;
+  SColumnInfo* colList;
+  int32_t queryTest;
+} SQueriedTableMeta;
+
 int32_t createQueryFuncExprFromMsg(SQueryTableMsg* pQueryMsg, int32_t numOfOutput, SExprInfo** pExprInfo,
-                                   SSqlFuncMsg** pExprMsg, SColumnInfo* pTagCols) {
+                                   SSqlFuncMsg** pExprMsg, SColumnInfo* pTagCols, bool isSuperTable) {
   *pExprInfo = NULL;
   int32_t code = TSDB_CODE_SUCCESS;
 
-  SExprInfo *pExprs = (SExprInfo *)calloc(pQueryMsg->numOfOutput, sizeof(SExprInfo));
+  SExprInfo *pExprs = (SExprInfo *)calloc(numOfOutput, sizeof(SExprInfo));
   if (pExprs == NULL) {
     return TSDB_CODE_QRY_OUT_OF_MEMORY;
   }
 
-  bool    isSuperTable = QUERY_IS_STABLE_QUERY(pQueryMsg->queryType);
+//  bool    isSuperTable = QUERY_IS_STABLE_QUERY(pQueryMsg->queryType);
   int16_t tagLen = 0;
 
   for (int32_t i = 0; i < numOfOutput; ++i) {