[TD-288] fix bug in join query.

src/client/inc/tscUtil.h

@@ -134,6 +134,7 @@ void tscFieldInfoSetBinExpr(SFieldInfo* pFieldInfo, int32_t index, SSqlFunctionE
 void tscFieldInfoCalOffset(SQueryInfo* pQueryInfo);
 void tscFieldInfoCopy(SFieldInfo* src, SFieldInfo* dst, const int32_t* indexList, int32_t size);
 void tscFieldInfoCopyAll(SFieldInfo* dst, SFieldInfo* src);
+void tscFieldInfoUpdateBySqlFunc(SQueryInfo* pQueryInfo);
 
 TAOS_FIELD* tscFieldInfoGetField(SQueryInfo* pQueryInfo, int32_t index);
 int16_t     tscFieldInfoGetOffset(SQueryInfo* pQueryInfo, int32_t index);

src/client/src/tscSQLParser.c

@@ -1998,17 +1998,16 @@ int32_t doGetColumnIndexByName(SSQLToken* pToken, SQueryInfo* pQueryInfo, SColum
 }
 
 int32_t getMeterIndex(SSQLToken* pTableToken, SQueryInfo* pQueryInfo, SColumnIndex* pIndex) {
+  pIndex->tableIndex = COLUMN_INDEX_INITIAL_VAL;
+  
   if (pTableToken->n == 0) {  // only one table and no table name prefix in column name
     if (pQueryInfo->numOfTables == 1) {
       pIndex->tableIndex = 0;
     }
-
+    
     return TSDB_CODE_SUCCESS;
   }
 
-  pIndex->tableIndex = COLUMN_INDEX_INITIAL_VAL;
-  char tableName[TSDB_METER_ID_LEN + 1] = {0};
-
   for (int32_t i = 0; i < pQueryInfo->numOfTables; ++i) {
     SMeterMetaInfo* pMeterMetaInfo = tscGetMeterMetaInfoFromQueryInfo(pQueryInfo, i);
     if (strncasecmp(pMeterMetaInfo->aliasName, pTableToken->z, pTableToken->n) == 0 &&
@@ -5662,7 +5661,7 @@ int32_t doCheckForQuery(SSqlObj* pSql, SQuerySQL* pQuerySql, int32_t index) {
       tscAddEmptyMeterMetaInfo(pQueryInfo);
     }
 
-    SMeterMetaInfo* pMeterInfo1 = tscGetMeterMetaInfoFromQueryInfo(pQueryInfo, i);
+    SMeterMetaInfo* pMeterInfo1 = tscGetMeterMetaInfoFromQueryInfo(pQueryInfo, i/2);
 
     SSQLToken t = {.type = TSDB_DATA_TYPE_BINARY, .n = pTableItem->nLen, .z = pTableItem->pz};
     if (setMeterID(pMeterInfo1, &t, pSql) != TSDB_CODE_SUCCESS) {

src/client/src/tscSecondaryMerge.c

@@ -259,8 +259,9 @@ void tscCreateLocalReducer(tExtMemBuffer **pMemBuffer, int32_t numOfBuffer, tOrd
   pReducer->rowSize = pMemBuffer[0]->nElemSize;
 
   tscRestoreSQLFunctionForMetricQuery(pQueryInfo);
+  tscFieldInfoUpdateBySqlFunc(pQueryInfo);
   tscFieldInfoCalOffset(pQueryInfo);
-
+  
   if (pReducer->rowSize > pMemBuffer[0]->pageSize) {
     assert(false);  // todo fixed row size is larger than the minimum page size;
   }

src/client/src/tscUtil.c

@@ -926,6 +926,20 @@ void tscFieldInfoSetBinExpr(SFieldInfo* pFieldInfo, int32_t index, SSqlFunctionE
   pFieldInfo->pExpr[index] = pExpr;
 }
 
+void tscFieldInfoUpdateBySqlFunc(SQueryInfo* pQueryInfo) {
+  for(int32_t i = 0; i < pQueryInfo->fieldsInfo.numOfOutputCols; ++i) {
+    TAOS_FIELD* field = tscFieldInfoGetField(pQueryInfo, i);
+    
+    SSqlExpr* pExpr = pQueryInfo->fieldsInfo.pSqlExpr[i];
+    if (pExpr == NULL) {
+      continue;
+    }
+    
+    field->type = pExpr->resType;
+    field->bytes = pExpr->resBytes;
+  }
+}
+
 void tscFieldInfoCalOffset(SQueryInfo* pQueryInfo) {
   SSqlExprInfo* pExprInfo = &pQueryInfo->exprsInfo;
   pExprInfo->pExprs[0]->offset = 0;
@@ -2012,6 +2026,7 @@ SSqlObj* createSubqueryObj(SSqlObj* pSql, int16_t tableIndex, void (*fp)(), void
     // create the fields info from the sql functions
     SColumnList columnList = {.num = 1};
   
+    // for avg/last/first/histo.. query, the output type is binary not numeric data type
     for(int32_t k = 0; k < numOfOutputCols; ++k) {
       SSqlExpr* pExpr = tscSqlExprGet(pQueryInfo, indexList[k]);
       columnList.ids[0] = (SColumnIndex){.tableIndex = tableIndex, .columnIndex = pExpr->colInfo.colIdx};