From 642beb069b9d78f7142202b3fb33f2cadf276021 Mon Sep 17 00:00:00 2001
From: Siyang Tang <82279870+TangSiyang2001@users.noreply.github.com>
Date: Thu, 15 Aug 2024 14:18:11 +0800
Subject: [PATCH] [fix](schema-change) Fix potential data race when a schema
 change jobs is set to cancelled but the table state is still SCHEMA_CHANGE
 (#39164) (#39327)

## Proposed changes

Set job cancel state after table state changed to normal.
---
 .../org/apache/doris/alter/SchemaChangeJobV2.java     | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/fe/fe-core/src/main/java/org/apache/doris/alter/SchemaChangeJobV2.java b/fe/fe-core/src/main/java/org/apache/doris/alter/SchemaChangeJobV2.java
index 86f0e24a62..e74754de75 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/alter/SchemaChangeJobV2.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/alter/SchemaChangeJobV2.java
@@ -657,7 +657,7 @@ public class SchemaChangeJobV2 extends AlterJobV2 {
             tbl.getIndexMetaByIndexId(shadowIdxId).setMaxColUniqueId(maxColUniqueId);
             if (LOG.isDebugEnabled()) {
                 LOG.debug("originIdxId:{}, shadowIdxId:{}, maxColUniqueId:{}, indexSchema:{}",
-                        originIdxId, shadowIdxId, maxColUniqueId,  indexSchemaMap.get(shadowIdxId));
+                        originIdxId, shadowIdxId, maxColUniqueId, indexSchemaMap.get(shadowIdxId));
             }
 
             tbl.deleteIndexInfo(originIdxName);
@@ -704,12 +704,11 @@ public class SchemaChangeJobV2 extends AlterJobV2 {
         pruneMeta();
         this.errMsg = errMsg;
         this.finishedTimeMs = System.currentTimeMillis();
-        LOG.info("cancel {} job {}, err: {}", this.type, jobId, errMsg);
-        Env.getCurrentEnv().getEditLog().logAlterJob(this);
-
         changeTableState(dbId, tableId, OlapTableState.NORMAL);
         LOG.info("set table's state to NORMAL when cancel, table id: {}, job id: {}", tableId, jobId);
-
+        jobState = JobState.CANCELLED;
+        Env.getCurrentEnv().getEditLog().logAlterJob(this);
+        LOG.info("cancel {} job {}, err: {}", this.type, jobId, errMsg);
         return true;
     }
 
@@ -745,8 +744,6 @@ public class SchemaChangeJobV2 extends AlterJobV2 {
                 }
             }
         }
-
-        jobState = JobState.CANCELLED;
     }
 
     // Check whether transactions of the given database which txnId is less than 'watershedTxnId' are finished.