ddl: add a warning after successfully reorganizing partitions (#42367)

close #42183

ddl/db_integration_test.go

@@ -4396,3 +4396,15 @@ func TestDisableDDL(t *testing.T) {
 	tk.MustGetErrCode("set @@global.tidb_enable_ddl=false;", errno.ErrDDLSetting)
 	tk.MustQuery("select @@global.tidb_enable_ddl").Check(testkit.Rows("1"))
 }
+
+func TestReorganizePartitionWarning(t *testing.T) {
+	// https://github.com/pingcap/tidb/issues/42183
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+
+	tk.MustExec("drop table if exists t")
+	tk.MustExec("create table t (id bigint, b varchar(20), index idxb(b)) partition by range(id) (partition p0 values less than (20), partition p1 values less than (100));")
+	tk.MustExec("alter table t reorganize partition p0 into (partition p01 values less than (10), partition p02 values less than (20));")
+	tk.MustQuery("show warnings").Check(testkit.Rows("Warning 1105 The statistics of related partitions will be outdated after reorganizing partitions. Please use 'ANALYZE TABLE' statement if you want to update it now"))
+}

ddl/ddl_api.go

@@ -4049,6 +4049,9 @@ func (d *ddl) ReorganizePartitions(ctx sessionctx.Context, ident ast.Ident, spec
 	// No preSplitAndScatter here, it will be done by the worker in onReorganizePartition instead.
 	err = d.DoDDLJob(ctx, job)
 	err = d.callHookOnChanged(job, err)
+	if err == nil {
+		ctx.GetSessionVars().StmtCtx.AppendWarning(errors.New("The statistics of related partitions will be outdated after reorganizing partitions. Please use 'ANALYZE TABLE' statement if you want to update it now"))
+	}
 	return errors.Trace(err)
 }
 

executor/autoidtest/BUILD.bazel

@@ -2,14 +2,14 @@ load("@io_bazel_rules_go//go:def.bzl", "go_test")
 
 go_test(
     name = "autoidtest_test",
-    timeout = "short",
+    timeout = "moderate",
     srcs = [
         "autoid_test.go",
         "main_test.go",
     ],
     flaky = True,
     race = "on",
-    shard_count = 10,
+    shard_count = 11,
     deps = [
         "//autoid_service",
         "//config",

executor/autoidtest/main_test.go

@@ -39,6 +39,7 @@ func TestMain(m *testing.M) {
 		goleak.IgnoreTopFunction("go.etcd.io/etcd/client/pkg/v3/logutil.(*MergeLogger).outputLoop"),
 		goleak.IgnoreTopFunction("gopkg.in/natefinch/lumberjack%2ev2.(*Logger).millRun"),
 		goleak.IgnoreTopFunction("github.com/tikv/client-go/v2/txnkv/transaction.keepAlive"),
+		goleak.IgnoreTopFunction("go.opencensus.io/stats/view.(*worker).start"),
 	}
 	goleak.VerifyTestMain(m, opts...)
 }

executor/simpletest/BUILD.bazel

@@ -10,7 +10,7 @@ go_test(
     ],
     flaky = True,
     race = "on",
-    shard_count = 34,
+    shard_count = 50,
     deps = [
         "//config",
         "//parser/auth",

sessionctx/sessionstates/BUILD.bazel

@@ -30,7 +30,7 @@ go_test(
     ],
     embed = [":sessionstates"],
     flaky = True,
-    shard_count = 2,
+    shard_count = 13,
     deps = [
         "//config",
         "//errno",