diff --git a/source/dnode/vnode/src/tsdb/tsdbSma.c b/source/dnode/vnode/src/tsdb/tsdbSma.c
index 5cfa597eb2375a4b34f22c9c7684c95a93ac9bc3..c5f1261282a89d9016d7d58927781a76db6ecc0a 100644
--- a/source/dnode/vnode/src/tsdb/tsdbSma.c
+++ b/source/dnode/vnode/src/tsdb/tsdbSma.c
@@ -86,7 +86,12 @@ static bool    tsdbSetAndOpenTSmaFile(STSmaReadH *pReadH, STSma *param, STimeWin
 
 static int32_t tsdbInitSmaStat(SSmaStat **pSmaStat) {
   ASSERT(pSmaStat != NULL);
-  // TODO: lock and create when each put, or create during tsdbNew.
+
+  if (*pSmaStat != NULL) {  // no lock
+    return TSDB_CODE_SUCCESS;
+  }
+
+  // TODO: lock. lazy mode when update expired window, or hungry mode during tsdbNew.
   if (*pSmaStat == NULL) {
     *pSmaStat = (SSmaStat *)calloc(1, sizeof(SSmaStat));
     if (*pSmaStat == NULL) {
@@ -149,6 +154,8 @@ int32_t tsdbUpdateExpiredWindow(STsdb *pTsdb, char *msg) {
     return TSDB_CODE_FAILED;
   }
 
+  tsdbInitSmaStat(&pTsdb->pSmaStat);  // lazy mode
+
   // TODO: decode the msg => start
   const char *  indexName = SMA_TEST_INDEX_NAME;
   const int32_t SMA_TEST_EXPIRED_WINDOW_SIZE = 10;
@@ -157,8 +164,8 @@ int32_t tsdbUpdateExpiredWindow(STsdb *pTsdb, char *msg) {
   for (int32_t i = 0; i < SMA_TEST_EXPIRED_WINDOW_SIZE; ++i) {
     expiredWindows[i] = now + i;
   }
-  // TODO: decode the msg <= end
 
+  // TODO: decode the msg <= end
   SHashObj *pItemsHash = pTsdb->pSmaStat->smaStatItems;
 
   SSmaStatItem *pItem = (SSmaStatItem *)taosHashGet(pItemsHash, indexName, strlen(indexName));
@@ -181,8 +188,12 @@ int32_t tsdbUpdateExpiredWindow(STsdb *pTsdb, char *msg) {
   int8_t state = TSDB_SMA_STAT_EXPIRED;
   for (int32_t i = 0; i < SMA_TEST_EXPIRED_WINDOW_SIZE; ++i) {
     if (taosHashPut(pItem->expiredWindows, &expiredWindows[i], sizeof(TSKEY), &state, sizeof(state)) != 0) {
-      // If error occurs during put expired windows, remove the smaIndex from pTsdb->pSmaStat, thus TSDB would tell
-      // query module to query raw TS data.
+      // If error occurs during taosHashPut expired windows, remove the smaIndex from pTsdb->pSmaStat, thus TSDB would
+      // tell query module to query raw TS data.
+      // N.B.
+      //  1) It is assumed to be extemely little probability event of fail to taosHashPut.
+      //  2) This would solve the inconsistency to some extent, but not completely, unless we record all expired
+      // windows failed to put into hash table.
       taosHashCleanup(pItem->expiredWindows);
       taosHashRemove(pItemsHash, indexName, sizeof(indexName));
       return TSDB_CODE_FAILED;
@@ -612,6 +623,22 @@ static bool tsdbSetAndOpenTSmaFile(STSmaReadH *pReadH, STSma *param, STimeWindow
  * @return int32_t
  */
 int32_t tsdbGetTSmaDataImpl(STsdb *pTsdb, STSma *param, STSmaData *pData, STimeWindow *queryWin, int32_t nMaxResult) {
+  const char *indexName = param->indexName;
+
+  SSmaStatItem *pItem = (SSmaStatItem *)taosHashGet(pTsdb->pSmaStat->smaStatItems, indexName, strlen(indexName));
+  if (pItem == NULL) {
+    // mark all window as expired and notify query module to query raw TS data.
+    return TSDB_CODE_SUCCESS;
+  }
+
+  int32_t nQueryWin = 0;
+  for (int32_t n = 0; n < nQueryWin; ++n) {
+    TSKEY thisWindow = n;
+    if (taosHashGet(pItem->expiredWindows, &thisWindow, sizeof(thisWindow)) != NULL) {
+      // TODO: mark this window as expired.
+    }
+  }
+
   STSmaReadH tReadH = {0};
   tsdbInitTSmaReadH(&tReadH, pTsdb, param, pData);