diff --git a/src/client/src/tscSQLParser.c b/src/client/src/tscSQLParser.c
index 981c1885e32951818eb48ac021eb72a5d5c3652a..c1268079ab0a9452316760e97a8dbf13dd7a79ec 100644
--- a/src/client/src/tscSQLParser.c
+++ b/src/client/src/tscSQLParser.c
@@ -3623,6 +3623,10 @@ int32_t setShowInfo(SSqlObj* pSql, struct SSqlInfo* pInfo) {
     if (pShowInfo->prefix.type == TK_STRING) {
       pShowInfo->prefix.n = stringProcess(pShowInfo->prefix.z, pShowInfo->prefix.n);
     }
+
+    if (pShowInfo->prefix.n <= 0) {
+      return invalidOperationMsg(tscGetErrorMsgPayload(pCmd), msg6);
+    }
   } 
   return TSDB_CODE_SUCCESS;
 }