From 85ccba0fab6a2bfa5ab6c407385fbd5b800484e6 Mon Sep 17 00:00:00 2001
From: Benguang Zhao <bgzhao@taosdata.com>
Date: Fri, 22 Mar 2024 15:27:22 +0800
Subject: [PATCH] enh: support changeless transaction of tasks

---
 source/dnode/mnode/impl/inc/mndDef.h   | 1 +
 source/dnode/mnode/impl/inc/mndTrans.h | 1 +
 source/dnode/mnode/impl/src/mndTrans.c | 4 +++-
 3 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/source/dnode/mnode/impl/inc/mndDef.h b/source/dnode/mnode/impl/inc/mndDef.h
index a63157445b..924af2b0a7 100644
--- a/source/dnode/mnode/impl/inc/mndDef.h
+++ b/source/dnode/mnode/impl/inc/mndDef.h
@@ -160,6 +160,7 @@ typedef struct {
   ETrnConflct   conflict;
   ETrnExec      exec;
   EOperType     oper;
+  bool          changeless;
   int32_t       code;
   int32_t       failedTimes;
   void*         rpcRsp;
diff --git a/source/dnode/mnode/impl/inc/mndTrans.h b/source/dnode/mnode/impl/inc/mndTrans.h
index 8689df98af..8c9ca87fb1 100644
--- a/source/dnode/mnode/impl/inc/mndTrans.h
+++ b/source/dnode/mnode/impl/inc/mndTrans.h
@@ -81,6 +81,7 @@ void    mndTransSetDbName(STrans *pTrans, const char *dbname, const char *stbnam
 void    mndTransSetArbGroupId(STrans *pTrans, int32_t groupId);
 void    mndTransSetSerial(STrans *pTrans);
 void    mndTransSetParallel(STrans *pTrans);
+void    mndTransSetChangeless(STrans *pTrans);
 void    mndTransSetOper(STrans *pTrans, EOperType oper);
 int32_t mndTransCheckConflict(SMnode *pMnode, STrans *pTrans);
 #ifndef BUILD_NO_CALL
diff --git a/source/dnode/mnode/impl/src/mndTrans.c b/source/dnode/mnode/impl/src/mndTrans.c
index 3af372a432..0e4f4210fb 100644
--- a/source/dnode/mnode/impl/src/mndTrans.c
+++ b/source/dnode/mnode/impl/src/mndTrans.c
@@ -739,6 +739,8 @@ void mndTransSetSerial(STrans *pTrans) { pTrans->exec = TRN_EXEC_SERIAL; }
 
 void mndTransSetParallel(STrans *pTrans) { pTrans->exec = TRN_EXEC_PARALLEL; }
 
+void mndTransSetChangeless(STrans *pTrans) { pTrans->changeless = true; }
+
 void mndTransSetOper(STrans *pTrans, EOperType oper) { pTrans->oper = oper; }
 
 static int32_t mndTransSync(SMnode *pMnode, STrans *pTrans) {
@@ -862,7 +864,7 @@ int32_t mndTransPrepare(SMnode *pMnode, STrans *pTrans) {
     return -1;
   }
 
-  if (taosArrayGetSize(pTrans->commitActions) <= 0) {
+  if (!pTrans->changeless && taosArrayGetSize(pTrans->commitActions) <= 0) {
     terrno = TSDB_CODE_MND_TRANS_CLOG_IS_NULL;
     mError("trans:%d, failed to prepare since %s", pTrans->id, terrstr());
     return -1;