[TD-6046]<fix> fix ts top/bottom index error when using order by

src/client/inc/tscUtil.h

@@ -213,6 +213,7 @@ SExprInfo* tscExprUpdate(SQueryInfo* pQueryInfo, int32_t index, int16_t function
                            int16_t size);
 
 size_t     tscNumOfExprs(SQueryInfo* pQueryInfo);
+size_t     tscExprTopBottomIndex(SQueryInfo* pQueryInfo);
 SExprInfo *tscExprGet(SQueryInfo* pQueryInfo, int32_t index);
 int32_t    tscExprCopy(SArray* dst, const SArray* src, uint64_t uid, bool deepcopy);
 int32_t    tscExprCopyAll(SArray* dst, const SArray* src, bool deepcopy);

src/client/src/tscSQLParser.c

@@ -5864,10 +5864,12 @@ int32_t validateOrderbyNode(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, SSqlNode* pSq
         pQueryInfo->order.orderColId = pSchema[index.columnIndex].colId;
       } else if (isTopBottomQuery(pQueryInfo)) {
         /* order of top/bottom query in interval is not valid  */
-        SExprInfo* pExpr = tscExprGet(pQueryInfo, 0);
+        size_t pos = tscExprTopBottomIndex(pQueryInfo);
+        assert(pos > 0);
+        SExprInfo* pExpr = tscExprGet(pQueryInfo, pos - 1);
         assert(pExpr->base.functionId == TSDB_FUNC_TS);
 
-        pExpr = tscExprGet(pQueryInfo, 1);
+        pExpr = tscExprGet(pQueryInfo, pos);
         if (pExpr->base.colInfo.colIndex != index.columnIndex && index.columnIndex != PRIMARYKEY_TIMESTAMP_COL_INDEX) {
           return invalidOperationMsg(tscGetErrorMsgPayload(pCmd), msg5);
         }
@@ -5949,10 +5951,12 @@ int32_t validateOrderbyNode(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, SSqlNode* pSq
         }
       } else {
         /* order of top/bottom query in interval is not valid  */
-        SExprInfo* pExpr = tscExprGet(pQueryInfo, 0);
+        size_t pos = tscExprTopBottomIndex(pQueryInfo);
+        assert(pos > 0);
+        SExprInfo* pExpr = tscExprGet(pQueryInfo, pos - 1);
         assert(pExpr->base.functionId == TSDB_FUNC_TS);
 
-        pExpr = tscExprGet(pQueryInfo, 1);
+        pExpr = tscExprGet(pQueryInfo, pos);
         if (pExpr->base.colInfo.colIndex != index.columnIndex && index.columnIndex != PRIMARYKEY_TIMESTAMP_COL_INDEX) {
           return invalidOperationMsg(tscGetErrorMsgPayload(pCmd), msg5);
         }

src/client/src/tscUtil.c

@@ -2427,6 +2427,17 @@ size_t tscNumOfExprs(SQueryInfo* pQueryInfo) {
   return taosArrayGetSize(pQueryInfo->exprList);
 }
 
+size_t tscExprTopBottomIndex(SQueryInfo* pQueryInfo){
+  size_t numOfExprs = tscNumOfExprs(pQueryInfo);
+  for(int32_t i = 0; i < numOfExprs; ++i) {
+    SExprInfo* pExpr = tscExprGet(pQueryInfo, i);
+    if (pExpr->base.functionId == TSDB_FUNC_TOP || pExpr->base.functionId == TSDB_FUNC_BOTTOM) {
+      return i;
+    }
+  }
+  return -1;
+}
+
 // todo REFACTOR
 void tscExprAddParams(SSqlExpr* pExpr, char* argument, int32_t type, int32_t bytes) {
   assert (pExpr != NULL || argument != NULL || bytes != 0);