statistics: rewrite unlock stats handler (#46478)

ref #46351

executor/lockstats/lock_stats_executor.go

@@ -50,14 +50,12 @@ func (e *LockExec) Next(_ context.Context, _ *chunk.Chunk) error {
 		return err
 	}
 
-	sv := e.Ctx().GetSessionVars()
-
-	msg, err := h.AddLockedTables(tids, pids, e.Tables, sv.MaxChunkSize)
+	msg, err := h.AddLockedTables(tids, pids, e.Tables)
 	if err != nil {
 		return err
 	}
 	if msg != "" {
-		sv.StmtCtx.AppendWarning(errors.New(msg))
+		e.Ctx().GetSessionVars().StmtCtx.AppendWarning(errors.New(msg))
 	}
 
 	return nil

statistics/handle/BUILD.bazel

@@ -11,6 +11,7 @@ go_library(
         "handle_hist.go",
         "historical_stats_handler.go",
         "lock_stats_handler.go",
+        "unlock_stats_handler.go",
         "update.go",
     ],
     importpath = "github.com/pingcap/tidb/statistics/handle",
@@ -67,7 +68,7 @@ go_test(
     embed = [":handle"],
     flaky = True,
     race = "on",
-    shard_count = 27,
+    shard_count = 29,
     deps = [
         "//config",
         "//domain",

statistics/handle/handletest/statslock/stats_lcok_test.go

@@ -76,7 +76,7 @@ func TestStatsLockAndUnlockTable(t *testing.T) {
 	require.Equal(t, int64(2), tblStats2.RealtimeCount)
 }
 
-func TestStatsLockTableRepeatedly(t *testing.T) {
+func TestStatsLockTableAndUnlockTableRepeatedly(t *testing.T) {
 	restore := config.RestoreFunc()
 	defer restore()
 	config.UpdateGlobal(func(conf *config.Config) {
@@ -113,14 +113,30 @@ func TestStatsLockTableRepeatedly(t *testing.T) {
 	// Lock the table again and check the warning.
 	tableLocked1 := handle.GetTableLockedAndClearForTest()
 	tk.MustExec("lock stats t")
-	tk.MustQuery("show warnings").Sort().Check(testkit.Rows(
+	tk.MustQuery("show warnings").Check(testkit.Rows(
 		"Warning 1105 skip locking locked table: test.t",
 	))
 
 	err = handle.LoadLockedTables()
 	require.Nil(t, err)
 	tableLocked2 := handle.GetTableLockedAndClearForTest()
 	require.Equal(t, tableLocked1, tableLocked2)
+
+	// Unlock the table.
+	tk.MustExec("unlock stats t")
+	rows = tk.MustQuery("select count(*) from mysql.stats_table_locked").Rows()
+	num, _ = strconv.Atoi(rows[0][0].(string))
+	require.Equal(t, num, 0)
+
+	tk.MustExec("analyze table test.t")
+	tblStats2 := handle.GetTableStats(tbl.Meta())
+	require.Equal(t, int64(2), tblStats2.RealtimeCount)
+
+	// Unlock the table again and check the warning.
+	tk.MustExec("unlock stats t")
+	tk.MustQuery("show warnings").Check(testkit.Rows(
+		"Warning 1105 skip unlocking unlocked table: test.t",
+	))
 }
 
 func TestStatsLockAndUnlockTables(t *testing.T) {