From 7c620dda79b2612fa721c775d04a046dae4d2c15 Mon Sep 17 00:00:00 2001
From: tangenta <tangenta@126.com>
Date: Wed, 7 Dec 2022 20:02:03 +0800
Subject: [PATCH] This is an automated cherry-pick of #39683

Signed-off-by: ti-chi-bot <ti-community-prow-bot@tidb.io>
---
 ddl/backfilling.go                                 |  9 ++++++++-
 .../realtikvtest/addindextest/integration_test.go  | 14 ++++++++++++++
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/ddl/backfilling.go b/ddl/backfilling.go
index be120e18c1465..6214a50b4a2e9 100644
--- a/ddl/backfilling.go
+++ b/ddl/backfilling.go
@@ -503,6 +503,7 @@ func (dc *ddlCtx) handleRangeTasks(scheduler *backfillScheduler, t table.Table,
 	job := reorgInfo.Job
 	source := getDDLRequestSource(job)
 	for i, keyRange := range kvRanges {
+		startKey := keyRange.StartKey
 		endKey := keyRange.EndKey
 		endK, err := getRangeEndKey(scheduler.jobCtx, dc.store, job.Priority, prefix, keyRange.StartKey, endKey)
 		if err != nil {
@@ -512,11 +513,17 @@ func (dc *ddlCtx) handleRangeTasks(scheduler *backfillScheduler, t table.Table,
 				zap.String("end key", hex.EncodeToString(endKey)), zap.String("current end key", hex.EncodeToString(endK)))
 			endKey = endK
 		}
+		if len(startKey) == 0 {
+			startKey = prefix
+		}
+		if len(endKey) == 0 {
+			endKey = prefix.PrefixNext()
+		}
 
 		task := &reorgBackfillTask{
 			id:              i,
 			physicalTableID: physicalTableID,
-			startKey:        keyRange.StartKey,
+			startKey:        startKey,
 			endKey:          endKey,
 			// If the boundaries overlap, we should ignore the preceding endKey.
 			endInclude: endK.Cmp(keyRange.EndKey) != 0 || i == len(kvRanges)-1,
diff --git a/tests/realtikvtest/addindextest/integration_test.go b/tests/realtikvtest/addindextest/integration_test.go
index d5159450c50c5..aa3bb0d0f68ba 100644
--- a/tests/realtikvtest/addindextest/integration_test.go
+++ b/tests/realtikvtest/addindextest/integration_test.go
@@ -261,12 +261,17 @@ func TestAddIndexIngestGeneratedColumns(t *testing.T) {
 	assertLastNDDLUseIngest(4)
 }
 
+<<<<<<< HEAD
 func TestAddIndexIngestRestoredData(t *testing.T) {
+=======
+func TestAddIndexIngestEmptyTable(t *testing.T) {
+>>>>>>> b6098ef6925 (ddl: assign table record prefix to start/end key if it is empty (#39683))
 	store := realtikvtest.CreateMockStoreAndSetup(t)
 	tk := testkit.NewTestKit(t, store)
 	tk.MustExec("drop database if exists addindexlit;")
 	tk.MustExec("create database addindexlit;")
 	tk.MustExec("use addindexlit;")
+<<<<<<< HEAD
 	tk.MustExec(`set global tidb_ddl_enable_fast_reorg=on;`)
 
 	tk.MustExec(`
@@ -283,11 +288,18 @@ func TestAddIndexIngestRestoredData(t *testing.T) {
 	tk.MustExec("INSERT INTO tbl_5 VALUES ('15:33:15','&U+x1',2007,'','Bob');")
 	tk.MustExec("alter table tbl_5 add unique key idx_13 ( col_23 );")
 	tk.MustExec("admin check table tbl_5;")
+=======
+	tk.MustExec("create table t (a int);")
+	tk.MustExec(`set global tidb_ddl_enable_fast_reorg=on;`)
+	tk.MustExec("alter table t add index idx(a);")
+
+>>>>>>> b6098ef6925 (ddl: assign table record prefix to start/end key if it is empty (#39683))
 	rows := tk.MustQuery("admin show ddl jobs 1;").Rows()
 	require.Len(t, rows, 1)
 	jobTp := rows[0][3].(string)
 	require.True(t, strings.Contains(jobTp, "ingest"), jobTp)
 }
+<<<<<<< HEAD
 
 func TestAddIndexIngestPanicOnCopRead(t *testing.T) {
 	store := realtikvtest.CreateMockStoreAndSetup(t)
@@ -388,3 +400,5 @@ func TestAddIndexIngestTimezone(t *testing.T) {
 	tk.MustExec("alter table t add index idx(t);")
 	tk.MustExec("admin check table t;")
 }
+=======
+>>>>>>> b6098ef6925 (ddl: assign table record prefix to start/end key if it is empty (#39683))