statistics: add a testcase for issue 54022 (#54137)

tests/realtikvtest/statisticstest/BUILD.bazel

@@ -10,8 +10,14 @@ go_test(
     flaky = True,
     race = "on",
     deps = [
+<<<<<<< HEAD
         "//statistics/handle",
         "//testkit",
+=======
+        "//pkg/parser/model",
+        "//pkg/statistics/asyncload",
+        "//pkg/testkit",
+>>>>>>> ba5c6a9bc6a (statistics: add a testcase for issue 54022 (#54137))
         "//tests/realtikvtest",
         "@com_github_stretchr_testify//require",
     ],

tests/realtikvtest/statisticstest/statistics_test.go

@@ -15,11 +15,19 @@
 package statisticstest
 
 import (
+	"context"
 	"fmt"
 	"testing"
+	"time"
 
+<<<<<<< HEAD
 	"github.com/pingcap/tidb/statistics/handle"
 	"github.com/pingcap/tidb/testkit"
+=======
+	"github.com/pingcap/tidb/pkg/parser/model"
+	"github.com/pingcap/tidb/pkg/statistics/asyncload"
+	"github.com/pingcap/tidb/pkg/testkit"
+>>>>>>> ba5c6a9bc6a (statistics: add a testcase for issue 54022 (#54137))
 	"github.com/pingcap/tidb/tests/realtikvtest"
 	"github.com/stretchr/testify/require"
 )
@@ -221,3 +229,70 @@ func checkFMSketch(tk *testkit.TestKit) {
 	tk.MustQuery(`SHOW STATS_HISTOGRAMS WHERE TABLE_NAME='employees' and partition_name="global"  and column_name="id"`).CheckAt([]int{6}, [][]any{
 		{"14"}})
 }
+
+func TestNoNeedIndexStatsLoading(t *testing.T) {
+	store, dom := realtikvtest.CreateMockStoreAndDomainAndSetup(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test;")
+	tk.MustExec("drop table if exists t;")
+	// 1. Create a table and the statsHandle.Update(do.InfoSchema()) will load this table into the stats cache.
+	tk.MustExec("create table if not exists t(a int, b int, index ia(a));")
+	// 2. Drop the stats of the stats, it will clean up all system table records for this table.
+	tk.MustExec("drop stats t;")
+	// 3. Insert some data and wait for the modify_count and the count is not null in the mysql.stats_meta.
+	tk.MustExec("insert into t value(1,1), (2,2);")
+	h := dom.StatsHandle()
+	require.NoError(t, h.DumpStatsDeltaToKV(true))
+	require.NoError(t, h.Update(dom.InfoSchema()))
+	// 4. Try to select some data from this table by ID, it would trigger an async load.
+	tk.MustExec("set tidb_opt_objective='determinate';")
+	tk.MustQuery("select * from t where a = 1 and b = 1;").Check(testkit.Rows("1 1"))
+	table, err := dom.InfoSchema().TableByName(model.NewCIStr("test"), model.NewCIStr("t"))
+	require.NoError(t, err)
+	checkTableIDInItems(t, table.Meta().ID)
+}
+
+func checkTableIDInItems(t *testing.T, tableID int64) {
+	ctx, cancel := context.WithTimeout(context.Background(), 1*time.Minute)
+	defer cancel()
+
+	ticker := time.NewTicker(2 * time.Millisecond)
+	defer ticker.Stop()
+
+	done := make(chan bool)
+
+	// First, confirm that the table ID is in the items.
+	items := asyncload.AsyncLoadHistogramNeededItems.AllItems()
+	for _, item := range items {
+		if item.TableID == tableID {
+			// Then, continuously check until it no longer exists or timeout.
+			go func() {
+				for {
+					select {
+					case <-ticker.C:
+						items := asyncload.AsyncLoadHistogramNeededItems.AllItems()
+						found := false
+						for _, item := range items {
+							if item.TableID == tableID {
+								found = true
+							}
+						}
+						if !found {
+							done <- true
+						}
+					case <-ctx.Done():
+						return
+					}
+				}
+			}()
+			break
+		}
+	}
+
+	select {
+	case <-done:
+		t.Log("Table ID has been removed from items")
+	case <-ctx.Done():
+		t.Fatal("Timeout: Table ID was not removed from items within the time limit")
+	}
+}