Set up docs MCPThese settings are available in system.merge_tree_settings and are autogenerated from the ClickHouse snapshot.
materialize_projections_on_insert
When enabled, INSERTs create new parts with projections. Otherwise, they can be created by explicit MATERIALIZE PROJECTION or during merges with materialize_projections_on_merge.
materialize_projections_on_merge
When enabled, a merge rebuilds a projection that is missing from all of its source parts (for example because they were
inserted with materialize_projections_on_insert = 0), so the merged part has the projection.
Merges still only combine parts that share the same set of projections. To backfill a projection to all existing parts, use an explicit MATERIALIZE PROJECTION. Projections are also created during INSERTs with materialize_projections_on_insert.