Change Details

The occurrence table (storing "the latest occurrence for a given origin") is redundant with occurrence_history and is a big source of churn on the primary database. As far as I can tell, this cache is seldom used, and will be made somewhat obsolete by the snapshot objects: unless we unfold the snapshot objects in the cache table (and therefore keep a table with a lot of churn), getting the latest visit for an origin will be just a matter of hitting an index once.

The occurrence and occurrence_history tables are a remnant of the pre-snapshot era of the archive. Most uses of these tables are for backwards-compatibility only. We should remove them.

The occurrence table (storing "the latest occurrence for a given origin") is redundant with occurrence_history and is a big source of churn on the primary databasand occurrence_history tables are a remnant of the pre-snapshot era of the archive. As far as I can tell, this cache is seldom used, and will be made somewhat obsolete by the snapshot objects: unless we unfold the snapshot objects in the cache table (and therefore keep a table with a lot of churn), getting the latest visit for an origin will be just a matter of hitting an index onceMost uses of these tables are for backwards-compatibility only. We should remove them.