executor: fix a panic when batch point get is used for partition table (#23652)

executor/batch_point_get.go

@@ -392,7 +392,7 @@ func (getter *PessimisticLockCacheGetter) Get(_ context.Context, key kv.Key) ([]
 }
 
 func getPhysID(tblInfo *model.TableInfo, val int64) int64 {
-	pi := tblInfo.Partition
+	pi := tblInfo.GetPartitionInfo()
 	if pi == nil {
 		return tblInfo.ID
 	}

executor/partition_table_test.go

@@ -15,6 +15,8 @@ package executor_test
 
 import (
 	. "github.com/pingcap/check"
+	"github.com/pingcap/parser/model"
+	"github.com/pingcap/tidb/infoschema"
 	"github.com/pingcap/tidb/util/testkit"
 )
 
@@ -65,3 +67,43 @@ func (s *testSuite9) TestPartitionReaderUnderApply(c *C) {
 		"4 hungry wilson 4.900000",
 		"5 naughty swartz 9.524000"))
 }
+
+func (s *testSuite9) TestPartitionInfoDisable(c *C) {
+	tk := testkit.NewTestKitWithInit(c, s.store)
+	tk.MustExec("use test")
+	tk.MustExec("drop table if exists t_info_null")
+	tk.MustExec(`CREATE TABLE t_info_null (
+  id bigint(20) unsigned NOT NULL AUTO_INCREMENT,
+  date date NOT NULL,
+  media varchar(32) NOT NULL DEFAULT '0',
+  app varchar(32) NOT NULL DEFAULT '',
+  xxx bigint(20) NOT NULL DEFAULT '0',
+  PRIMARY KEY (id, date),
+  UNIQUE KEY idx_media_id (media, date, app)
+) PARTITION BY RANGE COLUMNS(date) (
+  PARTITION p201912 VALUES LESS THAN ("2020-01-01"),
+  PARTITION p202001 VALUES LESS THAN ("2020-02-01"),
+  PARTITION p202002 VALUES LESS THAN ("2020-03-01"),
+  PARTITION p202003 VALUES LESS THAN ("2020-04-01"),
+  PARTITION p202004 VALUES LESS THAN ("2020-05-01"),
+  PARTITION p202005 VALUES LESS THAN ("2020-06-01"),
+  PARTITION p202006 VALUES LESS THAN ("2020-07-01"),
+  PARTITION p202007 VALUES LESS THAN ("2020-08-01"),
+  PARTITION p202008 VALUES LESS THAN ("2020-09-01"),
+  PARTITION p202009 VALUES LESS THAN ("2020-10-01"),
+  PARTITION p202010 VALUES LESS THAN ("2020-11-01"),
+  PARTITION p202011 VALUES LESS THAN ("2020-12-01")
+)`)
+	is := infoschema.GetInfoSchema(tk.Se)
+	tbl, err := is.TableByName(model.NewCIStr("test"), model.NewCIStr("t_info_null"))
+	c.Assert(err, IsNil)
+
+	tbInfo := tbl.Meta()
+	// Mock for a case that the tableInfo.Partition is not nil, but tableInfo.Partition.Enable is false.
+	// That may happen when upgrading from a old version TiDB.
+	tbInfo.Partition.Enable = false
+	tbInfo.Partition.Num = 0
+
+	// No panic.
+	tk.MustQuery("select * from t_info_null where (date = '2020-10-02' or date = '2020-10-06') and app = 'xxx' and media = '19003006'").Check(testkit.Rows())
+}

planner/core/cacheable_checker.go

@@ -131,7 +131,7 @@ func (checker *cacheableChecker) isPartitionTable(tn *ast.TableName) bool {
 		logutil.BgLogger().Error("Error occur in checking cacheable", zap.Error(err))
 		return false
 	}
-	if tb.Meta().Partition != nil {
+	if tb.Meta().GetPartitionInfo() != nil {
 		return true
 	}
 	return false