[TS-1318]<fix>: used merge sort to sort vgId and updated test cases

src/client/src/tscSubquery.c

@@ -936,6 +936,96 @@ static void setTidTagType(SJoinSupporter* p, uint8_t type) {
   }
 }
 
+static int32_t tidTagsMerge(SArray *arr, int32_t start, int32_t mid, int32_t end, const int32_t tagSize)
+{
+  char     *pTmp, *pRes = NULL;
+  char     *result = NULL;
+  STidTags *pi, *pj, *p;
+
+  int32_t k = 0;
+  int32_t i = start;
+  int32_t j = mid + 1;
+
+  if (end - start > 0) {
+    result = calloc(1, (end - start + 1) * tagSize);
+    if (result == NULL) {
+      tscError("failed to allocate memory for tidTagsMerge");
+      return TSDB_CODE_TSC_OUT_OF_MEMORY;
+    }
+  }
+
+  pRes = result;
+
+  while (i <= mid && j <= end) {
+    pi = taosArrayGet(arr, i);
+    pj = taosArrayGet(arr, j);
+
+    if (pi->vgId <= pj->vgId) {
+      p = taosArrayGet(arr, i++);
+      memcpy(pRes, p, tagSize);
+    } else {
+      p = taosArrayGet(arr, j++);
+      memcpy(pRes, p, tagSize);
+    }
+
+    k++;
+    pRes += tagSize;
+  }
+
+  if (i == mid + 1) {
+    while(j <= end) {
+      p = taosArrayGet(arr, j++);
+      memcpy(pRes, p, tagSize);
+      k++;
+      pRes += tagSize;
+    }
+  }
+
+  if (j == end + 1) {
+    while (i <= mid) {
+      p = taosArrayGet(arr, i++);
+      memcpy(pRes, p, tagSize);
+      k++;
+      pRes += tagSize;
+    }
+  }
+
+  for (i = start, j = 0, pTmp = result; j < k; i++, j++, pTmp += tagSize) {
+    p = (STidTags *) taosArrayGet(arr, i);
+    memcpy(p, pTmp, tagSize);
+  }
+
+  if (result) {
+    tfree(result);
+  }
+
+  return TSDB_CODE_SUCCESS;
+}
+
+static int32_t tidTagsMergeSort(SArray *arr, int32_t start, int32_t end, const int32_t tagSize)
+{
+  int32_t ret;
+  int32_t mid;
+
+  if (start >= end) {
+    return TSDB_CODE_SUCCESS;
+  }
+
+  mid = (start + end) / 2;
+
+  ret = tidTagsMergeSort(arr, start, mid, tagSize);
+  if (ret != TSDB_CODE_SUCCESS) {
+    return ret;
+  }
+
+  ret = tidTagsMergeSort(arr, mid + 1, end, tagSize);
+  if (ret != TSDB_CODE_SUCCESS) {
+    return ret;
+  }
+
+  return tidTagsMerge(arr, start, mid, end, tagSize);
+}
+
 static int32_t getIntersectionOfTableTuple(SQueryInfo* pQueryInfo, SSqlObj* pParentSql, SArray* resList) {
   int16_t joinNum = pParentSql->subState.numOfSub;
   STableMetaInfo* pTableMetaInfo = tscGetMetaInfo(pQueryInfo, 0);
@@ -1125,7 +1215,10 @@ static int32_t getIntersectionOfTableTuple(SQueryInfo* pQueryInfo, SSqlObj* pPar
     // sort according to the tag value
     size_t num = taosArrayGetSize(ctxlist[i].res);
 
-    qsort((ctxlist[i].res)->pData, num, size, tidTagsCompar);
+    int32_t ret = tidTagsMergeSort(ctxlist[i].res, 0, num - 1, size);
+    if (ret != TSDB_CODE_SUCCESS) {
+      return TSDB_CODE_TSC_OUT_OF_MEMORY;
+    }
 
     taosArrayPush(resList, &ctxlist[i].res);
 

tests/develop-test/2-query/function_unique.py

@@ -83,8 +83,8 @@ class TDTestCase:
         tdSql.checkData(3, 0, "2021-12-24 01:31:31")
         tdSql.checkData(0, 1, 1)
         tdSql.checkData(1, 1, 2)
-        tdSql.checkData(2, 1, 19)
-        tdSql.checkData(3, 1, 9)
+        tdSql.checkData(2, 1, 9)
+        tdSql.checkData(3, 1, 19)
 
         tdSql.query('select ts,unique(voltage),ts,groupid,location,tbname from unique')
         tdSql.checkRows(4)
@@ -106,19 +106,19 @@ class TDTestCase:
 
         tdSql.checkData(2, 0, "2021-12-24 01:31:31")
         tdSql.checkData(2, 1, "2021-12-24 01:31:31")
-        tdSql.checkData(2, 2, 19)
+        tdSql.checkData(2, 2, 9)
         tdSql.checkData(2, 3, "2021-12-24 01:31:31")
-        tdSql.checkData(2, 4, 2)
-        tdSql.checkData(2, 5, "Beijing.haidian")
-        tdSql.checkData(2, 6, "d002")
+        tdSql.checkData(2, 4, 3)
+        tdSql.checkData(2, 5, "Beijing.Tongzhou")
+        tdSql.checkData(2, 6, "d003")
 
         tdSql.checkData(3, 0, "2021-12-24 01:31:31")
         tdSql.checkData(3, 1, "2021-12-24 01:31:31")
-        tdSql.checkData(3, 2, 9)
+        tdSql.checkData(3, 2, 19)
         tdSql.checkData(3, 3, "2021-12-24 01:31:31")
-        tdSql.checkData(3, 4, 3)
-        tdSql.checkData(3, 5, "Beijing.Tongzhou")
-        tdSql.checkData(3, 6, "d003")
+        tdSql.checkData(3, 4, 2)
+        tdSql.checkData(3, 5, "Beijing.haidian")
+        tdSql.checkData(3, 6, "d002")
 
         tdSql.execute('insert into D004 values("2021-10-15 00:00:01", 10, 2) ("2021-12-24 00:21:31", 5, 2) ("2021-12-25 01:31:31", 9, 4)')
 
@@ -151,9 +151,9 @@ class TDTestCase:
         tdSql.query('select ts,unique(voltage) from unique group by ts')
         tdSql.checkRows(9)
         tdSql.checkData(1, 2, 1)
-        tdSql.checkData(4, 2, 1)
+        tdSql.checkData(4, 2, 2)
         tdSql.checkData(8, 2, 1)
-        tdSql.checkData(6, 2, 9)
+        tdSql.checkData(6, 2, 19)
         tdSql.checkData(7, 2, 9)
         #group by tag,column
         tdSql.query('select ts,unique(voltage) from unique group by location,num')
@@ -165,13 +165,13 @@ class TDTestCase:
         tdSql.query('select unique(voltage) from unique order by ts desc')
         tdSql.checkRows(6)
         tdSql.checkData(0, 0, "2021-12-24 01:31:31")
-        tdSql.checkData(0, 1, 9)
+        tdSql.checkData(0, 1, 19)
         tdSql.checkData(5, 0, "2021-10-15 00:00:01")
         tdSql.checkData(5, 1, 10)
         tdSql.query('select unique(voltage) from unique order by ts')
         tdSql.checkRows(6)
         tdSql.checkData(5, 0, "2021-12-24 01:31:31")
-        tdSql.checkData(5, 1, 9)
+        tdSql.checkData(5, 1, 19)
         tdSql.checkData(0, 0, "2021-10-15 00:00:01")
         tdSql.checkData(0, 1, 10)
         #order by column [desc]
@@ -216,7 +216,7 @@ class TDTestCase:
         tdSql.checkData(6, 0, "2021-12-25 01:31:31")
         tdSql.checkData(6, 1, 9)
         tdSql.checkData(0, 0, "2021-12-24 01:31:31")
-        tdSql.checkData(0, 1, 9)
+        tdSql.checkData(0, 1, 19)
 
         # error
         tdSql.error("select unique(ts) from unique")
@@ -246,7 +246,7 @@ class TDTestCase:
         tdSql.query('select unique(voltage) from unique where voltage > 2 limit 2 offset 1')
         tdSql.checkRows(2)
         tdSql.checkData(0, 1, 5)
-        tdSql.checkData(1, 1, 19)
+        tdSql.checkData(1, 1, 9)
 
         #having
         tdSql.query('select unique(voltage) from unique group by num having unique(voltage)>5')