Reads the current state of each of the derivation's sources from the host's own rows, in this transaction: connection generation, source version, retained message ids, source expiry and the pause and use switches. Leave out a source that is gone, and answer no source of an account the host is deleting. Never answer from a cache.
Deletes every host row stored for these result ids (saved marks, summaries and the like), whole.
Deletes the host's source content in the affected scope: text, metadata, passages and vectors.
Host/table bindings must operate only on the supplied transaction adapter. The store calls them inside its owner lock, in the transaction that commits, delivers or purges. Never fetch from a provider, parse, embed, generate or revoke inside them.