fix fill order by returned wrong values

source/libs/executor/src/filloperator.c

@@ -254,6 +254,8 @@ static SSDataBlock* doFillImpl(SOperatorInfo* pOperator) {
           (pInfo->pFillInfo->type != TSDB_FILL_NULL_F && pInfo->pFillInfo->type != TSDB_FILL_SET_VALUE_F)) {
         setOperatorCompleted(pOperator);
         return NULL;
+      } else if (pInfo->totalInputRows == 0 && taosFillNotStarted(pInfo->pFillInfo)) {
+        reviseFillStartAndEndKey(pInfo, order);
       }
 
       taosFillSetStartInfo(pInfo->pFillInfo, 0, pInfo->win.ekey);

source/libs/executor/src/tfill.c

@@ -207,7 +207,7 @@ static void doFillOneRow(SFillInfo* pFillInfo, SSDataBlock* pBlock, SSDataBlock*
             setNotFillColumn(pFillInfo, pDstCol, index, i);
           }
         } else {
-          SRowVal*    pRVal = FILL_IS_ASC_FILL(pFillInfo) ? &pFillInfo->prev : &pFillInfo->next;
+          SRowVal*    pRVal = &pFillInfo->prev;
           SGroupKeys* pKey = taosArrayGet(pRVal->pRowVal, i);
           if (IS_VAR_DATA_TYPE(type) || type == TSDB_DATA_TYPE_BOOL || pKey->isNull) {
             colDataSetNULL(pDstCol, index);
@@ -395,8 +395,8 @@ static int32_t fillResultImpl(SFillInfo* pFillInfo, SSDataBlock* pBlock, int32_t
       ASSERT(pFillInfo->currentKey == ts);
       int32_t index = pBlock->info.rows;
 
+      int32_t nextRowIndex = pFillInfo->index + 1;
       if (pFillInfo->type == TSDB_FILL_NEXT) {
-        int32_t nextRowIndex = pFillInfo->index + 1;
         if ((pFillInfo->index + 1) < pFillInfo->numOfRows) {
           copyCurrentRowIntoBuf(pFillInfo, nextRowIndex, &pFillInfo->next, false);
         } else {
@@ -404,6 +404,11 @@ static int32_t fillResultImpl(SFillInfo* pFillInfo, SSDataBlock* pBlock, int32_t
           copyCurrentRowIntoBuf(pFillInfo, nextRowIndex, &pFillInfo->next, true);
         }
       }
+      if (pFillInfo->type == TSDB_FILL_PREV) {
+        if (nextRowIndex + 1 >= pFillInfo->numOfRows && !FILL_IS_ASC_FILL(pFillInfo)) {
+          copyCurrentRowIntoBuf(pFillInfo, nextRowIndex, &pFillInfo->next, true);
+        }
+      }
 
       // copy rows to dst buffer
       for (int32_t i = 0; i < pFillInfo->numOfCols; ++i) {
@@ -418,7 +423,7 @@ static int32_t fillResultImpl(SFillInfo* pFillInfo, SSDataBlock* pBlock, int32_t
         if (!colDataIsNull_s(pSrc, pFillInfo->index)) {
           code = colDataSetVal(pDst, index, src, false);
           QUERY_CHECK_CODE(code, lino, _end);
-          SRowVal* pRVal = FILL_IS_ASC_FILL(pFillInfo) ? &pFillInfo->prev : &pFillInfo->next;
+          SRowVal* pRVal = &pFillInfo->prev;
           saveColData(pRVal->pRowVal, i, src, false);
           if (pFillInfo->srcTsSlotId == dstSlotId) {
             pRVal->key = *(int64_t*)src;
@@ -439,7 +444,7 @@ static int32_t fillResultImpl(SFillInfo* pFillInfo, SSDataBlock* pBlock, int32_t
               code = colDataSetVal(pDst, index, src, isNull);
               QUERY_CHECK_CODE(code, lino, _end);
 
-              SArray* p = FILL_IS_ASC_FILL(pFillInfo) ? pFillInfo->prev.pRowVal : pFillInfo->next.pRowVal;
+              SArray* p = pFillInfo->prev.pRowVal;
               saveColData(p, i, src, isNull);  // todo:
             } else if (pFillInfo->type == TSDB_FILL_NULL || pFillInfo->type == TSDB_FILL_NULL_F) {
               colDataSetNULL(pDst, index);

tests/system-test/2-query/fill.py

@@ -126,6 +126,17 @@ class TDTestCase:
     def test_fill_range(self):
         os.system('taosBenchmark -t 10 -n 10000 -v 8 -S 32000 -y')
         self.schedule_fill_test_tasks()
+        sql = "select first(_wstart), last(_wstart) from (select _wstart, count(*) from test.meters where ts >= '2019-09-19 23:54:00.000' and ts < '2019-09-20 01:00:00.000' interval(10s) sliding(10s) fill(VALUE_F, 122) order by _wstart) t"
+        tdSql.query(sql, queryTimes=1)
+        rows = tdSql.getRows()
+        first_ts = tdSql.queryResult[0][0]
+        last_ts = tdSql.queryResult[0][1]
+
+        sql = "select first(_wstart), last(_wstart) from (select _wstart, count(*) from test.meters where ts >= '2019-09-19 23:54:00.000' and ts < '2019-09-20 01:00:00.000' interval(10s) sliding(10s) fill(VALUE_F, 122) order by _wstart desc) t"
+        tdSql.query(sql, queryTimes=1)
+        tdSql.checkRows(rows)
+        tdSql.checkData(0, 0, first_ts)
+        tdSql.checkData(0, 1, last_ts)
         tdSql.execute('drop database test')
 
     def run(self):

tests/system-test/2-query/fill_with_group.py

@@ -165,7 +165,7 @@ class TDTestCase:
         sql = "select _wstart, count(*) from meters where ts >= '2018-09-20 00:00:00.000' and ts < '2018-09-20 01:00:00.000' interval(5m) fill(prev) order by _wstart desc;"
         tdSql.query(sql, queryTimes=1)
         tdSql.checkRows(12)
-        tdSql.checkData(0, 1, None)
+        tdSql.checkData(0, 1, 10)
         tdSql.checkData(1, 1, 10)
         tdSql.checkData(2, 1, 10)
         tdSql.checkData(3, 1, 10)
@@ -198,6 +198,45 @@ class TDTestCase:
         tdSql.query(sql, queryTimes=1)
         tdSql.checkRows(60)
 
+        sql = "select _wstart, count(*) from meters where ts >= '2018-09-19 23:54:00.000' and ts < '2018-09-20 01:00:00.000' interval(5m) fill(next) order by _wstart asc;"
+        tdSql.query(sql, queryTimes=1)
+        for i in range(0, 13):
+            tdSql.checkData(i, 1, 10)
+        tdSql.checkData(13, 1, None)
+        sql = "select _wstart, count(*) from meters where ts >= '2018-09-19 23:54:00.000' and ts < '2018-09-20 01:00:00.000' interval(5m) fill(next) order by _wstart desc;"
+        tdSql.query(sql, queryTimes=1)
+        tdSql.checkData(0, 1, None)
+        for i in range(1, 14):
+            tdSql.checkData(i, 1, 10)
+
+        sql = "select _wstart, count(*) from meters where ts >= '2018-09-19 23:54:00.000' and ts < '2018-09-20 01:00:00.000' interval(5m) fill(prev) order by _wstart asc;"
+        tdSql.query(sql, queryTimes=1)
+        tdSql.checkData(0, 1, None)
+        tdSql.checkData(1, 1, None)
+        for i in range(2, 14):
+            tdSql.checkData(i, 1, 10)
+        sql = "select _wstart, count(*) from meters where ts >= '2018-09-19 23:54:00.000' and ts < '2018-09-20 01:00:00.000' interval(5m) fill(prev) order by _wstart desc;"
+        tdSql.query(sql, queryTimes=1)
+        for i in range(0, 12):
+            tdSql.checkData(i, 1, 10)
+        tdSql.checkData(12, 1, None)
+        tdSql.checkData(13, 1, None)
+
+        sql = "select _wstart, count(*) from meters where ts >= '2018-09-19 23:54:00.000' and ts < '2018-09-20 01:00:00.000' interval(5m) fill(linear) order by _wstart asc;"
+        tdSql.query(sql, queryTimes=1)
+        tdSql.checkData(0, 1, None)
+        tdSql.checkData(1, 1, None)
+        for i in range(2, 13):
+            tdSql.checkData(i, 1, 10)
+        tdSql.checkData(13, 1, None)
+        sql = "select _wstart, count(*) from meters where ts >= '2018-09-19 23:54:00.000' and ts < '2018-09-20 01:00:00.000' interval(5m) fill(linear) order by _wstart desc;"
+        tdSql.query(sql, queryTimes=1)
+        tdSql.checkData(0, 1, None)
+        for i in range(1, 12):
+            tdSql.checkData(i, 1, 10)
+        tdSql.checkData(12, 1, None)
+        tdSql.checkData(13, 1, None)
+
     def run(self):
         self.prepareTestEnv()
         self.test_partition_by_with_interval_fill_prev_new_group_fill_error()