GeneratedColumn flag is missed when push down table scan to tiflash for partition table

[guo-shaoge]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

tidb/pkg/table/tables/tables.go

Lines 1781 to 1793 in 7569592

	func BuildPartitionTableScanFromInfos(tableInfo *model.TableInfo, columnInfos []*model.ColumnInfo, fastScan bool) *tipb.PartitionTableScan {
	pkColIDs := TryGetCommonPkColumnIds(tableInfo)
	tsExec := &tipb.PartitionTableScan{
	TableId: tableInfo.ID,
	Columns: util.ColumnsToProto(columnInfos, tableInfo.PKIsHandle, false, false),
	PrimaryColumnIds: pkColIDs,
	IsFastScan: &fastScan,
	}
	if tableInfo.IsCommonHandle {
	tsExec.PrimaryPrefixColumnIds = PrimaryPrefixColumnIDs(tableInfo)
	}
	return tsExec
	}

L1785 calls ColumnsToProto(), it assume isTiFlashStore is false(the last argument), which is wrong. Because tiflash can also call this function.

And the GeneratedColumnFlag will be missed because this bug, check

tidb/pkg/util/misc.go

Line 425 in 7569592

if isTiFlashStore && c.IsVirtualGenerated() {

In most case, tiflash will fill default value into this virtual generated column. But sometimes tiflash will not see the schema of virtual column (check #40663 (comment)), and issue/40663 will happen.

2. What did you expect to see? (Required)

3. What did you see instead (Required)

4. What is your TiDB version? (Required)

master 7569592

[guo-shaoge]

this bug is introduced by #55463