fix comment: fix auto_random & add it

br/pkg/lightning/restore/table_restore.go

@@ -683,7 +683,7 @@ func (tr *TableRestore) postProcess(
 		tblInfo := tr.tableInfo.Core
 		var err error
 		if tblInfo.PKIsHandle && tblInfo.ContainsAutoRandomBits() {
-			err = AlterAutoRandom(ctx, rc.tidbGlue.GetSQLExecutor(), tr.tableName, tr.alloc.Get(autoid.AutoRandomType).Base()+1)
+			err = AlterAutoRandom(ctx, rc.tidbGlue.GetSQLExecutor(), tr.tableName, uint64(tr.alloc.Get(autoid.AutoRandomType).Base())+1)
 		} else if common.TableHasAutoRowID(tblInfo) || tblInfo.GetAutoIncrementColInfo() != nil {
 			// only alter auto increment id iff table contains auto-increment column or generated handle
 			err = AlterAutoIncrement(ctx, rc.tidbGlue.GetSQLExecutor(), tr.tableName, uint64(tr.alloc.Get(autoid.RowIDAllocType).Base())+1)

br/pkg/lightning/restore/tidb.go

@@ -30,6 +30,7 @@ import (
 	"github.com/pingcap/tidb/br/pkg/lightning/log"
 	"github.com/pingcap/tidb/br/pkg/lightning/metric"
 	"github.com/pingcap/tidb/br/pkg/lightning/mydump"
+	"github.com/pingcap/tidb/meta/autoid"
 	"github.com/pingcap/tidb/parser"
 	"github.com/pingcap/tidb/parser/ast"
 	"github.com/pingcap/tidb/parser/format"
@@ -375,12 +376,16 @@ func ObtainNewCollationEnabled(ctx context.Context, g glue.SQLExecutor) (bool, e
 // the the auto incremanet base in tidb side, we needn't fetch currently auto increment value here.
 // See: https://github.com/pingcap/tidb/blob/64698ef9a3358bfd0fdc323996bb7928a56cadca/ddl/ddl_api.go#L2528-L2533
 func AlterAutoIncrement(ctx context.Context, g glue.SQLExecutor, tableName string, incr uint64) error {
+	var query string
 	logger := log.With(zap.String("table", tableName), zap.Uint64("auto_increment", incr))
 	if incr > math.MaxInt64 {
-		logger.Warn("auto_increment out of the maximum value TiDB supports", zap.Uint64("auto_increment", incr))
-		return nil
+		// automatically set max value
+		logger.Warn("auto_increment out of the maximum value TiDB supports, automatically set to the max", zap.Uint64("auto_increment", incr))
+		incr = math.MaxInt64
+		query = fmt.Sprintf("ALTER TABLE %s FORCE AUTO_INCREMENT=%d", tableName, incr)
+	} else {
+		query = fmt.Sprintf("ALTER TABLE %s AUTO_INCREMENT=%d", tableName, incr)
 	}
-	query := fmt.Sprintf("ALTER TABLE %s AUTO_INCREMENT=%d", tableName, incr)
 	task := logger.Begin(zap.InfoLevel, "alter table auto_increment")
 	err := g.ExecuteWithLog(ctx, query, "alter table auto_increment", logger)
 	task.End(zap.ErrorLevel, err)
@@ -393,8 +398,17 @@ func AlterAutoIncrement(ctx context.Context, g glue.SQLExecutor, tableName strin
 	return errors.Annotatef(err, "%s", query)
 }
 
-func AlterAutoRandom(ctx context.Context, g glue.SQLExecutor, tableName string, randomBase int64) error {
-	logger := log.With(zap.String("table", tableName), zap.Int64("auto_random", randomBase))
+func AlterAutoRandom(ctx context.Context, g glue.SQLExecutor, tableName string, randomBase uint64) error {
+	logger := log.With(zap.String("table", tableName), zap.Uint64("auto_random", randomBase))
+	// according to https://docs.pingcap.com/zh/tidb/dev/auto-random
+	// auto_random_base is related to shard_bits from (0, 15]
+	// which can be specified by users.
+	// To make the random_base always valid, we conservatively set it to 15.
+	maxRandom := 1<<(64-autoid.MaxAutoRandomBits-1) - 1 // one bit for sign
+	if randomBase > uint64(maxRandom) {
+		logger.Warn("auto_random out of the maximum value TiDB supports, automatically set to the max", zap.Uint64("auto_random", randomBase))
+		return nil
+	}
 	query := fmt.Sprintf("ALTER TABLE %s AUTO_RANDOM_BASE=%d", tableName, randomBase)
 	task := logger.Begin(zap.InfoLevel, "alter table auto_random")
 	err := g.ExecuteWithLog(ctx, query, "alter table auto_random_base", logger)

br/pkg/lightning/restore/tidb_test.go

@@ -405,13 +405,16 @@ func TestAlterAutoInc(t *testing.T) {
 	s.mockDB.
 		ExpectExec("\\QALTER TABLE `db`.`table` AUTO_INCREMENT=12345\\E").
 		WillReturnResult(sqlmock.NewResult(1, 1))
+	s.mockDB.
+		ExpectExec("\\QALTER TABLE `db`.`table` FORCE AUTO_INCREMENT=9223372036854775807\\E").
+		WillReturnResult(sqlmock.NewResult(1, 1))
 	s.mockDB.
 		ExpectClose()
 
 	err := AlterAutoIncrement(ctx, s.tiGlue.GetSQLExecutor(), "`db`.`table`", 12345)
 	require.NoError(t, err)
 
-	err = AlterAutoIncrement(ctx, s.tiGlue.GetSQLExecutor(), "`db`.`table`", uint64(math.MaxInt64+1))
+	err = AlterAutoIncrement(ctx, s.tiGlue.GetSQLExecutor(), "`db`.`table`", uint64(math.MaxInt64)+1)
 	require.NoError(t, err)
 }
 
@@ -428,6 +431,9 @@ func TestAlterAutoRandom(t *testing.T) {
 
 	err := AlterAutoRandom(ctx, s.tiGlue.GetSQLExecutor(), "`db`.`table`", 12345)
 	require.NoError(t, err)
+
+	err = AlterAutoRandom(ctx, s.tiGlue.GetSQLExecutor(), "`db`.`table`", uint64(math.MaxInt64)+1)
+	require.NoError(t, err)
 }
 
 func TestObtainRowFormatVersionSucceed(t *testing.T) {

br/tests/lightning_max_incr/config.toml

@@ -0,0 +1,2 @@
+[tikv-importer]
+backend = 'local'

br/tests/lightning_max_incr/data/db-schema-create.sql

@@ -0,0 +1 @@
+create database db;

br/tests/lightning_max_incr/data/db.test-schema.sql

@@ -0,0 +1,5 @@
+create table test(
+    a bigint auto_increment,
+    b int,
+    primary key(a)
+);

br/tests/lightning_max_incr/data/db.test.000000000.csv

@@ -0,0 +1,3 @@
+"a","b"
+1,2
+9223372036854775807,3

br/tests/lightning_max_incr/data/db.test1-schema.sql

@@ -0,0 +1,5 @@
+create table test1(
+    a bigint auto_random,
+    b int,
+    primary key(a)
+);

br/tests/lightning_max_incr/data/db.test1.000000000.csv

@@ -0,0 +1,3 @@
+"a","b"
+1,2
+9223372036854775807,3

br/tests/lightning_max_incr/run.sh

@@ -0,0 +1,47 @@
+#!/bin/sh
+#
+# Copyright 2022 PingCAP, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -eux
+
+check_cluster_version 4 0 0 'local backend' || exit 0
+
+ENGINE_COUNT=6
+
+check_result() {
+    run_sql 'SHOW DATABASES;'
+    check_contains 'Database: db';
+    run_sql 'SHOW TABLES IN db;'
+    check_contains 'Tables_in_db: test'
+    check_contains 'Tables_in_db: test1'
+    run_sql 'SELECT count(*) FROM db.test;'
+    check_contains: 'count(*): 2'
+    run_sql 'SELECT count(*) FROM db.test1;'
+    check_contains: 'count(*): 2'
+}
+
+cleanup() {
+    rm -f $TEST_DIR/lightning.log
+    rm -rf $TEST_DIR/sst
+    run_sql 'DROP DATABASE IF EXISTS db;'
+}
+
+cleanup
+
+run_lightning --sorted-kv-dir "$TEST_DIR/sst" --config "tests/$TEST_NAME/config.toml" --log-file "$TEST_DIR/lightning.log"
+check_result
+run_sql 'INSERT INTO db.test(b) VALUES(11);'
+check_contains 'ERROR'
+cleanup