[CASSANDRA-12852] Add allow_deletes table schema option, which defaults to True

• Type: Improvement
• Status: Open
• Priority: Low
• Resolution: Unresolved
• Component/s: Legacy/Core
• Assignee: Unassigned
• Reporter: Joaquin Casares
• Created: 27/Oct/16 16:57
• Updated: 16/Apr/19 09:30

Description

We see the need for this table schema option frequently in production systems, at both my current and previous job, to prevent disastrous zombie data cases where gc_grace_seconds is set to 0 for the life of the table. An example would be a write-only table with a default TTL and tombstones that won't clear fast enough.

Whenever I set gc_grace_seconds to 0, I typically update the comments to let any future users know that you shouldn't send deletes to that table, but I always fear that application developers will rarely read the production schema comments. When allow_deletes is set to False for a table, Cassandra would ideally throw an exception at ingestion time for delete mutations.

This would ensure that my previous assumption of a write-only table holds true as well as alert any future developers of that table's mutation restrictions.

Issue Links

• is related to: CASSANDRA-9779 Append-only optimization