From 6e593be4225358ad0bba0a6df8a3220fbb1f3c35 Mon Sep 17 00:00:00 2001
From: you06 <you1474600@gmail.com>
Date: Fri, 4 Aug 2023 20:44:39 +0800
Subject: [PATCH] executor: fix load data assertion failure (#43858) (#45825)

---
 server/server_test.go  | 70 ++++++++++++++++++++++++++++++++++++++++++
 server/tidb_test.go    |  5 +++
 table/tables/tables.go |  3 +-
 3 files changed, 77 insertions(+), 1 deletion(-)

diff --git a/server/server_test.go b/server/server_test.go
index 623a4d3313628..b585e8b17bcaf 100644
--- a/server/server_test.go
+++ b/server/server_test.go
@@ -2381,3 +2381,73 @@ func (cli *testServerClient) runTestInfoschemaClientErrors(t *testing.T) {
 		}
 	})
 }
+
+func (cli *testServerClient) runTestLoadDataReplace(t *testing.T) {
+	fp1, err := os.CreateTemp("", "a.dat")
+	require.NoError(t, err)
+	require.NotNil(t, fp1)
+	path1 := fp1.Name()
+	fp2, err := os.CreateTemp("", "b.dat")
+	require.NoError(t, err)
+	require.NotNil(t, fp2)
+	path2 := fp2.Name()
+	defer func() {
+		err = fp1.Close()
+		require.NoError(t, err)
+		err = os.Remove(path1)
+		require.NoError(t, err)
+
+		err = fp2.Close()
+		require.NoError(t, err)
+		err = os.Remove(path2)
+		require.NoError(t, err)
+	}()
+
+	_, err = fp1.WriteString(
+		"1,abc\n" +
+			"2,cdef\n" +
+			"3,asdf\n")
+	require.NoError(t, err)
+	_, err = fp2.WriteString(
+		"1,AAA\n" +
+			"2,BBB\n" +
+			"3,asdf\n" +
+			"4,444\n")
+	require.NoError(t, err)
+
+	expects := []struct {
+		col1 int64
+		col2 string
+	}{
+		{1, "AAA"},
+		{2, "BBB"},
+		{3, "asdf"},
+		{4, "444"},
+	}
+
+	cli.runTestsOnNewDB(t, func(config *mysql.Config) {
+		config.AllowAllFiles = true
+		config.Params["sql_mode"] = "''"
+	}, "LoadData", func(dbt *testkit.DBTestKit) {
+		dbt.MustExec("create table t1(id int, name varchar(20), primary key(id) clustered);")
+		_, err = dbt.GetDB().Exec(fmt.Sprintf(`load data local infile '%s' replace into table t1 fields terminated by ',' enclosed by '' (id,name)`, path1))
+		require.NoError(t, err)
+		_, err = dbt.GetDB().Exec(fmt.Sprintf(`load data local infile '%s' replace into table t1 fields terminated by ',' enclosed by '' (id,name)`, path2))
+		require.NoError(t, err)
+		var (
+			a sql.NullInt64
+			b sql.NullString
+		)
+		rows := dbt.MustQuery("select * from t1 order by id asc")
+		for _, expect := range expects {
+			require.Truef(t, rows.Next(), "unexpected data")
+			err = rows.Scan(&a, &b)
+			require.NoError(t, err)
+			require.Equal(t, expect.col1, a.Int64)
+			require.Equal(t, expect.col2, b.String)
+			err = rows.Scan(&a, &b)
+			require.NoError(t, err)
+		}
+		require.Falsef(t, rows.Next(), "expect end")
+	})
+}
diff --git a/server/tidb_test.go b/server/tidb_test.go
index a9cf74347a56f..30e4ea814927f 100644
--- a/server/tidb_test.go
+++ b/server/tidb_test.go
@@ -3210,3 +3210,8 @@ func TestProxyProtocolWithIpNoFallbackable(t *testing.T) {
 	require.NotNil(t, err)
 	db.Close()
 }
+
+func TestLoadData(t *testing.T) {
+	ts := createTidbTestSuite(t)
+	ts.runTestLoadDataReplace(t)
+}
diff --git a/table/tables/tables.go b/table/tables/tables.go
index da20b1647fbd8..a18896ce07f94 100644
--- a/table/tables/tables.go
+++ b/table/tables/tables.go
@@ -882,7 +882,8 @@ func (t *TableCommon) AddRecord(sctx sessionctx.Context, r []types.Datum, opts .
 			}
 		}
 	})
-	if setPresume && !txn.IsPessimistic() {
+	// batch-check guarantees the existence of key itself.
+	if setPresume && !txn.IsPessimistic() || sctx.GetSessionVars().StmtCtx.BatchCheck {
 		err = txn.SetAssertion(key, kv.SetAssertUnknown)
 	} else {
 		err = txn.SetAssertion(key, kv.SetAssertNotExist)