finish basic function for tail

src/client/src/tscUtil.c

@@ -5121,7 +5121,6 @@ int32_t tscCreateQueryFromQueryInfo(SQueryInfo* pQueryInfo, SQueryAttr* pQueryAt
   }
 
   pQueryAttr->uniqueQuery       = isFunctionQuery(numOfOutput, pQueryAttr->pExpr1, TSDB_FUNC_UNIQUE);
-  pQueryAttr->tailQuery         = isFunctionQuery(numOfOutput, pQueryAttr->pExpr1, TSDB_FUNC_TAIL);
 
   pQueryAttr->tableCols = calloc(numOfCols, sizeof(SColumnInfo));
   for(int32_t i = 0; i < numOfCols; ++i) {

src/query/inc/qExecutor.h

@@ -224,7 +224,6 @@ typedef struct SQueryAttr {
   bool             stableQuery;      // super table query or not
   bool             topBotQuery;      // TODO used bitwise flag
   bool             uniqueQuery;
-  bool             tailQuery;
   bool             groupbyColumn;    // denote if this is a groupby normal column query
   bool             hasTagResults;    // if there are tag values in final result or not
   bool             timeWindowInterpo;// if the time window start/end required interpolation

src/query/src/qExecutor.c

@@ -9589,7 +9589,6 @@ SQInfo* createQInfoImpl(SQueryTableMsg* pQueryMsg, SGroupbyExpr* pGroupbyExpr, S
   pQueryAttr->pFilters        = pFilters;
   pQueryAttr->range           = pQueryMsg->range;
   pQueryAttr->uniqueQuery     = isFunctionQuery(numOfOutput, pExprs, TSDB_FUNC_UNIQUE);
-  pQueryAttr->tailQuery       = isFunctionQuery(numOfOutput, pExprs, TSDB_FUNC_TAIL);
 
   pQueryAttr->tableCols = calloc(numOfCols, sizeof(SSingleColumnFilterInfo));
   if (pQueryAttr->tableCols == NULL) {