diff --git a/src/client/src/tscSQLParser.c b/src/client/src/tscSQLParser.c
index 77c37239daea1b898d2ec8835f83d29000cc1fa2..f82e1b62e95a9cfcce7ecc946cc03ec4ae604eb4 100644
--- a/src/client/src/tscSQLParser.c
+++ b/src/client/src/tscSQLParser.c
@@ -8005,6 +8005,28 @@ static void freeElem(void* p) {
   tfree(*(char**)p);
 }
 
+int32_t tnameComparFn(const void* p1, const void* p2) {
+  SName* pn1 = (SName*)p1;
+  SName* pn2 = (SName*)p2;
+
+  int32_t ret = strncmp(pn1->acctId, pn2->acctId, tListLen(pn1->acctId));
+  if (ret != 0) {
+    return ret > 0? 1:-1;
+  } else {
+    ret = strncmp(pn1->dbname, pn2->dbname, tListLen(pn1->dbname));
+    if (ret != 0) {
+      return ret > 0? 1:-1;
+    } else {
+      ret = strncmp(pn1->tname, pn2->tname, tListLen(pn1->tname));
+      if (ret != 0) {
+        return ret > 0? 1:-1;
+      } else {
+        return 0;
+      }
+    }
+  }
+}
+
 int32_t loadAllTableMeta(SSqlObj* pSql, struct SSqlInfo* pInfo) {
   SSqlCmd* pCmd = &pSql->cmd;
 
@@ -8055,6 +8077,9 @@ int32_t loadAllTableMeta(SSqlObj* pSql, struct SSqlInfo* pInfo) {
   plist = taosArrayInit(4, POINTER_BYTES);
   pVgroupList = taosArrayInit(4, POINTER_BYTES);
 
+  taosArraySort(tableNameList, tnameComparFn);
+  taosArrayRemoveDuplicate(tableNameList, tnameComparFn, NULL);
+
   size_t numOfTables = taosArrayGetSize(tableNameList);
   for (int32_t i = 0; i < numOfTables; ++i) {
     SName* pname = taosArrayGet(tableNameList, i);
@@ -8075,8 +8100,7 @@ int32_t loadAllTableMeta(SSqlObj* pSql, struct SSqlInfo* pInfo) {
           continue;
         }
       } else if (pTableMeta->tableType == TSDB_SUPER_TABLE) {
-        // the vgroup list of a super table is not kept in local buffer, so here need retrieve it
-        // from the mnode each time
+        // the vgroup list of super table is not kept in local buffer, so here need retrieve it from the mnode each time
         char* t = strdup(name);
         taosArrayPush(pVgroupList, &t);
       }
@@ -8103,6 +8127,7 @@ int32_t loadAllTableMeta(SSqlObj* pSql, struct SSqlInfo* pInfo) {
   if (pInfo->funcs) {
     funcSize = taosArrayGetSize(pInfo->funcs);
   }
+
   if (funcSize > 0) {
     for (size_t i = 0; i < funcSize; ++i) {
       SStrToken* t = taosArrayGet(pInfo->funcs, i);
diff --git a/src/client/src/tscUtil.c b/src/client/src/tscUtil.c
index 6ae024932935afdd9ac3e4eb909a65790d5d69fe..5b291c6e1fd94d445bc0397b3926e0523e17dd58 100644
--- a/src/client/src/tscUtil.c
+++ b/src/client/src/tscUtil.c
@@ -1315,8 +1315,7 @@ void tscFreeQueryInfo(SSqlCmd* pCmd, bool removeMeta) {
     return;
   }
 
-  SQueryInfo* pQueryInfo = tscGetQueryInfo(pCmd);
-
+  SQueryInfo* pQueryInfo = pCmd->pQueryInfo;
   while(pQueryInfo != NULL) {
     SQueryInfo* p = pQueryInfo->sibling;
 
@@ -1596,7 +1595,7 @@ void freeUdfInfo(SUdfInfo* pUdfInfo) {
   taosCloseDll(pUdfInfo->handle);
 }
 
-
+// todo refactor
 void*  tscDestroyUdfArrayList(SArray* pUdfList) {
   if (pUdfList == NULL) {
     return NULL;
@@ -2986,6 +2985,7 @@ void tscInitQueryInfo(SQueryInfo* pQueryInfo) {
 int32_t tscAddQueryInfo(SSqlCmd* pCmd) {
   assert(pCmd != NULL);
   SQueryInfo* pQueryInfo = calloc(1, sizeof(SQueryInfo));
+
   if (pQueryInfo == NULL) {
     return TSDB_CODE_TSC_OUT_OF_MEMORY;
   }
@@ -3968,17 +3968,21 @@ void tscTryQueryNextClause(SSqlObj* pSql, __async_cb_func_t fp) {
   //backup the total number of result first
   int64_t num = pRes->numOfTotal + pRes->numOfClauseTotal;
 
-
   // DON't free final since it may be recoreded and used later in APP
   TAOS_FIELD* finalBk = pRes->final;
   pRes->final = NULL;
   tscFreeSqlResult(pSql);
+
   pRes->final = finalBk;
-  
   pRes->numOfTotal = num;
-  
+
+  for(int32_t i = 0; i < pSql->subState.numOfSub; ++i) {
+    taos_free_result(pSql->pSubs[i]);
+  }
+
   tfree(pSql->pSubs);
   pSql->subState.numOfSub = 0;
+
   pSql->fp = fp;
 
   tscDebug("0x%"PRIx64" try data in the next subclause", pSql->self);
@@ -4618,6 +4622,20 @@ int32_t nameComparFn(const void* n1, const void* n2) {
   }
 }
 
+static void freeContent(void* p) {
+  char* ptr = *(char**)p;
+  tfree(ptr);
+}
+
+static int32_t contCompare(const void* p1, const void* p2) {
+  int32_t ret = strcmp(p1, p2);
+  if (ret == 0) {
+    return 0;
+  } else {
+    return ret > 0 ? 1:-1;
+  }
+}
+
 int tscTransferTableNameList(SSqlObj *pSql, const char *pNameList, int32_t length, SArray* pNameArray) {
   SSqlCmd *pCmd = &pSql->cmd;
 
@@ -4665,32 +4683,7 @@ int tscTransferTableNameList(SSqlObj *pSql, const char *pNameList, int32_t lengt
   }
 
   taosArraySort(pNameArray, nameComparFn);
-
-  int32_t pos = 0;
-  for(int32_t i = 1; i < len; ++i) {
-    char** p1 = taosArrayGet(pNameArray, pos);
-    char** p2 = taosArrayGet(pNameArray, i);
-
-    if (strcmp(*p1, *p2) == 0) {
-      // do nothing
-    } else {
-      if (pos + 1 != i) {
-        char* p = taosArrayGetP(pNameArray, pos + 1);
-        tfree(p);
-        taosArraySet(pNameArray, pos + 1, p2);
-        pos += 1;
-      } else {
-        pos += 1;
-      }
-    }
-  }
-
-  for(int32_t i = pos + 1; i < pNameArray->size; ++i) {
-    char* p = taosArrayGetP(pNameArray, i);
-    tfree(p);
-  }
-
-  pNameArray->size = pos + 1;
+  taosArrayRemoveDuplicate(pNameArray, contCompare, freeContent);
   return TSDB_CODE_SUCCESS;
 }
 
diff --git a/src/util/CMakeLists.txt b/src/util/CMakeLists.txt
index 27d9e11053f16c70e0bc6cac411c5db43eb93462..44808b102581f5e4298adea36e9eb74de72042e8 100644
--- a/src/util/CMakeLists.txt
+++ b/src/util/CMakeLists.txt
@@ -11,7 +11,7 @@ TARGET_LINK_LIBRARIES(tutil pthread os lz4 z rmonotonic)
 
 IF (TD_LINUX)
   TARGET_LINK_LIBRARIES(tutil m rt)
-#  ADD_SUBDIRECTORY(tests)
+  ADD_SUBDIRECTORY(tests)
 
   FIND_PATH(ICONV_INCLUDE_EXIST iconv.h /usr/include/ /usr/local/include/)
   IF (ICONV_INCLUDE_EXIST)
diff --git a/src/util/inc/tarray.h b/src/util/inc/tarray.h
index 97aeaa61d4734d258212117cf2e948f7a087baf7..2da74eac820e28206cb3e2b7cb6f2c4fb9f481b8 100644
--- a/src/util/inc/tarray.h
+++ b/src/util/inc/tarray.h
@@ -60,6 +60,13 @@ void *taosArrayAddBatch(SArray *pArray, const void *pData, int nEles);
  */
 void taosArrayRemoveBatch(SArray *pArray, const int32_t* pData, int32_t numOfElems);
 
+/**
+ *
+ * @param pArray
+ * @param comparFn
+ * @param fp
+ */
+void taosArrayRemoveDuplicate(SArray *pArray, __compar_fn_t comparFn, void (*fp)(void*));
 
 /**
  *  add all element from the source array list into the destination
diff --git a/src/util/src/tarray.c b/src/util/src/tarray.c
index d25d547be1c879df10024b9fb8141b27ba3dd1f8..d0d126c1e4d7f2e7c0913585df6031b556291fc3 100644
--- a/src/util/src/tarray.c
+++ b/src/util/src/tarray.c
@@ -124,6 +124,46 @@ void taosArrayRemoveBatch(SArray *pArray, const int32_t* pData, int32_t numOfEle
   pArray->size -= numOfElems;
 }
 
+void taosArrayRemoveDuplicate(SArray *pArray, __compar_fn_t comparFn, void (*fp)(void*)) {
+  assert(pArray);
+
+  size_t size = pArray->size;
+  if (size <= 1) {
+    return;
+  }
+
+  int32_t pos = 0;
+  for(int32_t i = 1; i < size; ++i) {
+    char* p1 = taosArrayGet(pArray, pos);
+    char* p2 = taosArrayGet(pArray, i);
+
+    if (comparFn(p1, p2) == 0) {
+      // do nothing
+    } else {
+      if (pos + 1 != i) {
+        void* p = taosArrayGet(pArray, pos + 1);
+        if (fp != NULL) {
+          fp(p);
+        }
+
+        taosArraySet(pArray, pos + 1, p2);
+        pos += 1;
+      } else {
+        pos += 1;
+      }
+    }
+  }
+
+  if (fp != NULL) {
+    for(int32_t i = pos + 1; i < pArray->size; ++i) {
+      void* p = taosArrayGet(pArray, i);
+      fp(p);
+    }
+  }
+
+  pArray->size = pos + 1;
+}
+
 void* taosArrayAddAll(SArray* pArray, const SArray* pInput) {
   return taosArrayAddBatch(pArray, pInput->pData, (int32_t) taosArrayGetSize(pInput));
 }
diff --git a/tests/script/sh/prepare_udf.sh b/tests/script/sh/prepare_udf.sh
index ecfc53660ee33c65540638354c4f44119b76034d..a856b96c987ff63dd2c19a30ff007be9cd5b17f9 100644
--- a/tests/script/sh/prepare_udf.sh
+++ b/tests/script/sh/prepare_udf.sh
@@ -5,6 +5,7 @@ echo -n "" > /tmp/empty
 dd if=/dev/zero bs=3584 of=/tmp/big count=1
 
 rm -rf /tmp/sum_double.so /tmp/add_one.so
+touch /tmp/normal
 
 gcc -g -O0 -fPIC -shared sh/sum_double.c -o /tmp/sum_double.so
 gcc -g -O0 -fPIC -shared sh/add_one.c -o /tmp/add_one.so