provider is the caller's bound provider; without one the store uses the default.
Optionalprovider: IMetadataProviderEvery field row for one object, including disabled ones, for the same reason.
Whether this connection has a per-connection catalog at all. Cheap existence check.
Every object row for a connection, INCLUDING disabled ones.
Disabled rows are load-bearing here: the overlay reactivates an object that reappeared rather than inserting a second one, and the unique constraint on (connection, name) means matching active rows only would turn a reappearance into a constraint violation.
Reads and writes for the per-connection catalog.