feat: not allowed to set WAL_RETENTION_PERIOD as zero when there are topics defined

source/dnode/mnode/impl/inc/mndTopic.h

@@ -32,6 +32,7 @@ bool         mndTopicExistsForDb(SMnode *pMnode, SDbObj *pDb);
 const char  *mndTopicGetShowName(const char topic[TSDB_TOPIC_FNAME_LEN]);
 
 int32_t mndSetTopicCommitLogs(SMnode *pMnode, STrans *pTrans, SMqTopicObj *pTopic);
+int32_t mndGetNumOfTopics(SMnode *pMnode, char *dbName, int32_t *pNumOfTopics);
 
 #ifdef __cplusplus
 }

source/dnode/mnode/impl/src/mndDb.c

@@ -849,6 +849,18 @@ static int32_t mndProcessAlterDbReq(SRpcMsg *pReq) {
     goto _OVER;
   }
 
+  int32_t numOfTopics = 0;
+  if (mndGetNumOfTopics(pMnode, pDb->name, &numOfTopics) != 0) {
+    goto _OVER;
+  }
+
+  if (numOfTopics != 0 && alterReq.walRetentionPeriod == 0) {
+    terrno = TSDB_CODE_MND_INVALID_DB_OPTION;
+    mError("db:%s, not allowed to set WAL_RETENTION_PERIOD 0 when there are topics defined. numOfTopics:%d", pDb->name,
+           numOfTopics);
+    goto _OVER;
+  }
+
   memcpy(&dbObj, pDb, sizeof(SDbObj));
   if (dbObj.cfg.pRetensions != NULL) {
     dbObj.cfg.pRetensions = taosArrayDup(pDb->cfg.pRetensions, NULL);

source/dnode/mnode/impl/src/mndTopic.c

@@ -793,7 +793,7 @@ static int32_t mndProcessDropTopicReq(SRpcMsg *pReq) {
   return TSDB_CODE_ACTION_IN_PROGRESS;
 }
 
-static int32_t mndGetNumOfTopics(SMnode *pMnode, char *dbName, int32_t *pNumOfTopics) {
+int32_t mndGetNumOfTopics(SMnode *pMnode, char *dbName, int32_t *pNumOfTopics) {
   *pNumOfTopics = 0;
 
   SSdb   *pSdb = pMnode->pSdb;
@@ -943,4 +943,4 @@ int32_t mndDropTopicByDB(SMnode *pMnode, STrans *pTrans, SDbObj *pDb) {
 
   return code;
 }
-#endif
\ No newline at end of file
+#endif