extension_drop

Run custom commands when an extension is dropped. By default, DROP EXTENSION simply drops all the objects the extension owns; this lets you register additional SQL to run when a given extension is dropped.

Requires cat_tools >= 0.2.1.

Functions

None of these are granted to PUBLIC except where noted, since extension_drop__add/extension_drop__update let the caller register arbitrary SQL to run later. Grant them to specific roles as needed.

• extension_drop__add(extension_name name, sql text) RETURNS void Register sql to run when extension_name is dropped.

• extension_drop__update(extension_name name, sql text) RETURNS void Replace the SQL registered for extension_name.

• extension_drop__remove(extension_name name) RETURNS void Remove the SQL registered for extension_name.

• extension_drop__get(extension_name name) RETURNS extension_drop__commands Look up the row (extension_name, sql) registered for extension_name. Granted to PUBLIC by default.

• extension_drop__sanity_check(ignore name DEFAULT NULL) RETURNS name[] Returns the names of extensions that have registered drop commands but no longer exist. Should always return an empty array; pass an extension name via ignore to exclude it from the check (useful while dropping that extension). Granted to PUBLIC by default.

• extension_drop__sanity_assert(ignore name DEFAULT NULL) RETURNS void Raises an error if extension_drop__sanity_check() (called with the same ignore argument) isn't empty. Granted to PUBLIC by default.

• extension_drop__repair() RETURNS void Deletes any stale rows found by extension_drop__sanity_check(). This should never be needed in normal operation.

How it works

An event trigger (extension_drop, on sql_drop) fires whenever an extension is dropped, runs any SQL registered for it via extension_drop__add/extension_drop__update, and removes the registration afterward.