flashback: fix realtikvtest/flashbacktest test cases (#52899) (#55288)

close #52898

Makefile

@@ -761,6 +761,14 @@ bazel_pipelineddmltest: failpoint-enable bazel_ci_simple_prepare
 		-- //tests/realtikvtest/pipelineddmltest/...
 	./build/jenkins_collect_coverage.sh
 
+# on timeout, bazel won't print log sometimes, so we use --test_output=all to print log always
+.PHONY: bazel_flashbacktest
+bazel_flashbacktest: failpoint-enable bazel_ci_simple_prepare
+	bazel $(BAZEL_GLOBAL_CONFIG) coverage $(BAZEL_CMD_CONFIG) $(BAZEL_INSTRUMENTATION_FILTER) --test_output=all --test_arg=-with-real-tikv --define gotags=deadlock,intest \
+	--@io_bazel_rules_go//go/config:cover_format=go_cover \
+		-- //tests/realtikvtest/flashbacktest/...
+	./build/jenkins_collect_coverage.sh
+
 .PHONY: bazel_lint
 bazel_lint: bazel_prepare
 	bazel build //... --//build:with_nogo_flag=true

pkg/statistics/handle/ddl/ddl.go

@@ -55,20 +55,25 @@ func (h *ddlHandlerImpl) HandleDDLEvent(t *util.DDLEvent) error {
 		return err
 	}
 	defer h.statsHandler.SPool().Put(sctx)
-	if isSysDB, err := t.IsMemOrSysDB(sctx.(sessionctx.Context)); err != nil {
-		return err
-	} else if isSysDB {
-		// EXCHANGE PARTITION EVENT NOTES:
-		// 1. When a partition is exchanged with a system table, we need to adjust the global statistics
-		//    based on the count delta and modify count delta. However, due to the involvement of the system table,
-		//    a complete update of the global statistics is not feasible. Therefore, we bypass the statistics update
-		//    for the table in this scenario. Despite this, the table id still changes, so the statistics for the
-		//    system table will still be visible.
-		// 2. If the system table is a partitioned table, we will update the global statistics for the partitioned table.
-		//    It is rare to exchange a partition from a system table, so we can ignore this case. In this case,
-		//    the system table will have statistics, but this is not a significant issue.
-		logutil.StatsLogger().Info("Skip handle system database ddl event", zap.Stringer("event", t))
-		return nil
+
+	// ActionFlashbackCluster will not create any new stats info
+	// and it's SchemaID alwayws equals to 0, so skip check it.
+	if t.GetType() != model.ActionFlashbackCluster {
+		if isSysDB, err := t.IsMemOrSysDB(sctx.(sessionctx.Context)); err != nil {
+			return err
+		} else if isSysDB {
+			// EXCHANGE PARTITION EVENT NOTES:
+			// 1. When a partition is exchanged with a system table, we need to adjust the global statistics
+			//    based on the count delta and modify count delta. However, due to the involvement of the system table,
+			//    a complete update of the global statistics is not feasible. Therefore, we bypass the statistics update
+			//    for the table in this scenario. Despite this, the table id still changes, so the statistics for the
+			//    system table will still be visible.
+			// 2. If the system table is a partitioned table, we will update the global statistics for the partitioned table.
+			//    It is rare to exchange a partition from a system table, so we can ignore this case. In this case,
+			//    the system table will have statistics, but this is not a significant issue.
+			logutil.StatsLogger().Info("Skip handle system database ddl event", zap.Stringer("event", t))
+			return nil
+		}
 	}
 	logutil.StatsLogger().Info("Handle ddl event", zap.Stringer("event", t))
 

tests/realtikvtest/flashbacktest/flashback_test.go

@@ -429,6 +429,7 @@ func TestFlashbackSequence(t *testing.T) {
 		require.Equal(t, res[0][0], "101")
 
 		require.NoError(t, failpoint.Disable("github.com/pingcap/tidb/pkg/ddl/injectSafeTS"))
+		tk.MustExec("drop sequence seq")
 	}
 }