diff --git a/source/dnode/vnode/src/tsdb/tsdbRead.c b/source/dnode/vnode/src/tsdb/tsdbRead.c
index 655177a3628e87301d5483b0f58d7ff6da993a1f..da6fad6bcdfcdb251c0a5ebbcc9c53584945bc01 100644
--- a/source/dnode/vnode/src/tsdb/tsdbRead.c
+++ b/source/dnode/vnode/src/tsdb/tsdbRead.c
@@ -155,6 +155,7 @@ typedef struct SBlockInfoBuf {
   int32_t currentIndex;
   SArray* pData;
   int32_t numPerBucket;
+  int32_t numOfTables;
 } SBlockInfoBuf;
 
 struct STsdbReader {
@@ -300,6 +301,47 @@ static int32_t initBlockScanInfoBuf(SBlockInfoBuf* pBuf, int32_t numOfTables) {
     taosArrayPush(pBuf->pData, &p);
   }
 
+  pBuf->numOfTables = numOfTables;
+
+  return TSDB_CODE_SUCCESS;
+}
+
+static int32_t ensureBlockScanInfoBuf(SBlockInfoBuf* pBuf, int32_t numOfTables) {
+  if (numOfTables <= pBuf->numOfTables) {
+    return TSDB_CODE_SUCCESS;
+  }
+
+  if (pBuf->numOfTables > 0) {
+    STableBlockScanInfo *p = (STableBlockScanInfo*)taosArrayPop(pBuf->pData);
+    taosMemoryFree(p);
+    pBuf->numOfTables /= pBuf->numPerBucket;
+  }
+  
+  int32_t num = (numOfTables - pBuf->numOfTables) / pBuf->numPerBucket;
+  int32_t remainder = (numOfTables - pBuf->numOfTables) % pBuf->numPerBucket;
+  if (pBuf->pData == NULL) {
+    pBuf->pData = taosArrayInit(num + 1, POINTER_BYTES);
+  }
+
+  for (int32_t i = 0; i < num; ++i) {
+    char* p = taosMemoryCalloc(pBuf->numPerBucket, sizeof(STableBlockScanInfo));
+    if (p == NULL) {
+      return TSDB_CODE_OUT_OF_MEMORY;
+    }
+
+    taosArrayPush(pBuf->pData, &p);
+  }
+
+  if (remainder > 0) {
+    char* p = taosMemoryCalloc(remainder, sizeof(STableBlockScanInfo));
+    if (p == NULL) {
+      return TSDB_CODE_OUT_OF_MEMORY;
+    }
+    taosArrayPush(pBuf->pData, &p);
+  }
+
+  pBuf->numOfTables = numOfTables;
+
   return TSDB_CODE_SUCCESS;
 }
 
@@ -3738,8 +3780,12 @@ int32_t tsdbSetTableList(STsdbReader* pReader, const void* pTableList, int32_t n
     clearBlockScanInfo(*p);
   }
 
-  // todo handle the case where size is less than the value of num
-  ASSERT(size >= num);
+  if (size < num) {
+    int32_t code = ensureBlockScanInfoBuf(&pReader->blockInfoBuf, num);
+    if (code) {
+      return code;
+    }
+  }
 
   taosHashClear(pReader->status.pTableMap);
   STableUidList* pUidList = &pReader->status.uidList;
diff --git a/tests/parallel_test/cases.task b/tests/parallel_test/cases.task
index 188ab86944dafe350d72fe0cc8554131ad4c8bbe..fb15e57fec62b2d454e5a6b9b95a01968a2cb4e6 100644
--- a/tests/parallel_test/cases.task
+++ b/tests/parallel_test/cases.task
@@ -179,7 +179,8 @@
 ,,y,script,./test.sh -f tsim/query/sys_tbname.sim
 ,,y,script,./test.sh -f tsim/query/groupby.sim
 ,,y,script,./test.sh -f tsim/query/forceFill.sim
-,,n,script,./test.sh -f tsim/query/join.sim
+,,y,script,./test.sh -f tsim/query/join.sim
+,,y,script,./test.sh -f tsim/query/partitionby.sim
 ,,y,script,./test.sh -f tsim/qnode/basic1.sim
 ,,y,script,./test.sh -f tsim/snode/basic1.sim
 ,,y,script,./test.sh -f tsim/mnode/basic1.sim
diff --git a/tests/script/tsim/query/partitionby.sim b/tests/script/tsim/query/partitionby.sim
new file mode 100644
index 0000000000000000000000000000000000000000..8babd1aa8de8e0ad943312e6712d297c3c5242b4
--- /dev/null
+++ b/tests/script/tsim/query/partitionby.sim
@@ -0,0 +1,39 @@
+system sh/stop_dnodes.sh
+system sh/deploy.sh -n dnode1 -i 1
+system sh/exec.sh -n dnode1 -s start
+sql connect
+
+$dbPrefix = db
+$tbPrefix1 = tba
+$tbPrefix2 = tbb
+$mtPrefix = stb
+$tbNum = 10
+$rowNum = 2
+
+print =============== step1
+$i = 0
+$db = $dbPrefix . $i
+$mt1 = $mtPrefix . $i
+$i = 1
+$mt2 = $mtPrefix . $i
+
+sql drop database $db -x step1
+step1:
+sql create database $db vgroups 3
+sql use $db
+sql create table $mt1 (ts timestamp, f1 int) TAGS(tag1 int, tag2 binary(500))
+sql create table tb0 using $mt1 tags(0, 'a');
+sql create table tb1 using $mt1 tags(1, 'b');
+sql create table tb2 using $mt1 tags(1, 'a');
+sql create table tb3 using $mt1 tags(1, 'a');
+sql create table tb4 using $mt1 tags(3, 'b');
+sql create table tb5 using $mt1 tags(3, 'a');
+sql create table tb6 using $mt1 tags(3, 'b');
+sql create table tb7 using $mt1 tags(3, 'b');
+
+sql select * from $mt1 partition by tag1,tag2 limit 1;
+if $rows != 0 then
+  return -1
+endi
+
+system sh/exec.sh -n dnode1 -s stop -x SIGINT