[TS-802]<bug>(query): fixed first last problem with order by

src/client/src/tscUtil.c

@@ -1340,6 +1340,18 @@ void handleDownstreamOperator(SSqlObj** pSqlObjList, int32_t numOfUpstream, SQue
           break;
         }
       }
+
+      // set input data order to param[1]
+      if(pex->base.functionId == TSDB_FUNC_FIRST || pex->base.functionId  ==  TSDB_FUNC_FIRST_DST ||
+         pex->base.functionId == TSDB_FUNC_LAST  || pex->base.functionId  ==  TSDB_FUNC_LAST) {
+        // set input order
+        SQueryInfo* pInputQI = pSqlObjList[0]->cmd.pQueryInfo;
+        if(pInputQI) {
+          pex->base.numOfParams = 2;
+          pex->base.param[1].nType = TSDB_DATA_TYPE_INT;
+          pex->base.param[1].i64 = pInputQI->order.order;
+        }
+      }
     }
 
     tscDebug("0x%"PRIx64" create QInfo 0x%"PRIx64" to execute the main query while all nest queries are ready", pSql->self, pSql->self);

src/query/src/qAggMain.c

@@ -698,10 +698,6 @@ static int32_t dataBlockRequired(SQLFunctionCtx *pCtx, STimeWindow* w, int32_t c
 
 // todo: if column in current data block are null, opt for this case
 static int32_t firstFuncRequired(SQLFunctionCtx *pCtx, STimeWindow* w, int32_t colId) {
-  if (pCtx->order == TSDB_ORDER_DESC) {
-    return BLK_DATA_NO_NEEDED;
-  }
-  
   // no result for first query, data block is required
   if (GET_RES_INFO(pCtx) == NULL || GET_RES_INFO(pCtx)->numOfRes <= 0) {
     return BLK_DATA_ALL_NEEDED;
@@ -710,11 +706,7 @@ static int32_t firstFuncRequired(SQLFunctionCtx *pCtx, STimeWindow* w, int32_t c
   }
 }
 
-static int32_t lastFuncRequired(SQLFunctionCtx *pCtx, STimeWindow* w, int32_t colId) {
-  if (pCtx->order != pCtx->param[0].i64) {
-    return BLK_DATA_NO_NEEDED;
-  }
-  
+static int32_t lastFuncRequired(SQLFunctionCtx *pCtx, STimeWindow* w, int32_t colId) {  
   if (GET_RES_INFO(pCtx) == NULL || GET_RES_INFO(pCtx)->numOfRes <= 0) {
     return BLK_DATA_ALL_NEEDED;
   } else {
@@ -1523,15 +1515,20 @@ static bool first_last_function_setup(SQLFunctionCtx *pCtx, SResultRowCellInfo*
 }
 
 // todo opt for null block
-static void first_function(SQLFunctionCtx *pCtx) {
-  if (pCtx->order == TSDB_ORDER_DESC) {
-    return;
-  }
-  
+static void first_function(SQLFunctionCtx *pCtx) {  
   int32_t notNullElems = 0;
+  int32_t step = 1;
+  int32_t i = 0;
+
+  if(pCtx->numOfParams == 2)   {
+    if(pCtx->param[1].nType == TSDB_DATA_TYPE_INT && pCtx->param[1].i64 == TSDB_ORDER_DESC) {
+      step = -1;
+      i = pCtx->size - 1;
+    }
+  }
   
   // handle the null value
-  for (int32_t i = 0; i < pCtx->size; ++i) {
+  for (int32_t m = 0; m < pCtx->size; ++m, i+=step) {
     char *data = GET_INPUT_DATA(pCtx, i);
     if (pCtx->hasNull && isNull(data, pCtx->inputType)) {
       continue;
@@ -1634,16 +1631,20 @@ static void first_dist_func_merge(SQLFunctionCtx *pCtx) {
  *    least one data in this block that is not null.(TODO opt for this case)
  */
 static void last_function(SQLFunctionCtx *pCtx) {
-  if (pCtx->order != pCtx->param[0].i64) {
-    return;
-  }
-
   SResultRowCellInfo* pResInfo = GET_RES_INFO(pCtx);
-
   int32_t notNullElems = 0;
-  if (pCtx->order == TSDB_ORDER_DESC) {
+  int32_t step = -1;
+  int32_t i = pCtx->size - 1;
 
-    for (int32_t i = pCtx->size - 1; i >= 0; --i) {
+  if(pCtx->numOfParams == 2)   {
+    if(pCtx->param[1].nType == TSDB_DATA_TYPE_INT && pCtx->param[1].i64 == TSDB_ORDER_DESC) {
+      step = 1;
+      i = 0;
+    }
+  }
+
+  if (pCtx->order == TSDB_ORDER_DESC) {
+    for (int32_t m = pCtx->size - 1; m >= 0; --m, i += step) {
       char *data = GET_INPUT_DATA(pCtx, i);
       if (pCtx->hasNull && isNull(data, pCtx->inputType) && (!pCtx->requireNull)) {
         continue;
@@ -1660,7 +1661,7 @@ static void last_function(SQLFunctionCtx *pCtx) {
       break;
     }
   } else {  // ascending order
-    for (int32_t i = pCtx->size - 1; i >= 0; --i) {
+    for (int32_t m = pCtx->size - 1; m >= 0; --m, i += step) {
       char *data = GET_INPUT_DATA(pCtx, i);
       if (pCtx->hasNull && isNull(data, pCtx->inputType) && (!pCtx->requireNull)) {
         continue;

src/query/src/qExecutor.c

@@ -1910,7 +1910,7 @@ static int32_t getGroupbyColumnIndex(SGroupbyExpr *pGroupbyExpr, SSDataBlock* pD
 
 static bool functionNeedToExecute(SQueryRuntimeEnv *pRuntimeEnv, SQLFunctionCtx *pCtx) {
   SResultRowCellInfo *pResInfo = GET_RES_INFO(pCtx);
-  SQueryAttr* pQueryAttr = pRuntimeEnv->pQueryAttr;
+  //SQueryAttr* pQueryAttr = pRuntimeEnv->pQueryAttr;
 
   // in case of timestamp column, always generated results.
   int32_t functionId = pCtx->functionId;
@@ -1922,14 +1922,14 @@ static bool functionNeedToExecute(SQueryRuntimeEnv *pRuntimeEnv, SQLFunctionCtx
     return false;
   }
 
-  if (functionId == TSDB_FUNC_FIRST_DST || functionId == TSDB_FUNC_FIRST) {
-    return QUERY_IS_ASC_QUERY(pQueryAttr);
-  }
+  //if (functionId == TSDB_FUNC_FIRST_DST || functionId == TSDB_FUNC_FIRST) {
+    //return QUERY_IS_ASC_QUERY(pQueryAttr);
+  //}
 
   // denote the order type
-  if ((functionId == TSDB_FUNC_LAST_DST || functionId == TSDB_FUNC_LAST)) {
-    return pCtx->param[0].i64 == pQueryAttr->order.order;
-  }
+  //if ((functionId == TSDB_FUNC_LAST_DST || functionId == TSDB_FUNC_LAST)) {
+  //  return pCtx->param[0].i64 == pQueryAttr->order.order;
+  //}
 
   // in the reverse table scan, only the following functions need to be executed
   if (IS_REVERSE_SCAN(pRuntimeEnv) ||