Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

It may occurs with a small probability under the following scenario

1. change column type to a wider column type
2. insert some data into the new column that exceeds the range of the old column type
3. doing many truncate table
   The reason may be that if a table is truncated, then it become a tombstone table in tiflash. And tiflash has two schema sync mode: incremental sync and full sync. If the schema version changed a lot, then it will trigger a full sync. But the tombstone table schema change is not showed in the full sync list, so it's schema change cannot be seen. And tiflash cannot use the old schema to decode the new data.

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

tiflash works normally

3. What did you see instead (Required)

tiflash crash

4. What is your TiFlash version? (Required)

the problem may influence all version