Use case
A user implements manual replication of data and wants to validate checksums automatically in efficient manner. ClickHouse always calculates checksums for all data and this information is already available internally.

Describe the solution you'd like
Add columns named column_data_compressed_checksum, column_data_uncompressed_checksum. column_marks_checksum.

For implementation, look at MergeTreeDataPartChecksum struct and StorageSystemPartsColumns.