First half of escaping for LIKE special characters % and _ before preparing for SQL.

Handler for updating the current site’s posts count when a post is deleted.

Handler for updating the current site’s posts count when a post status changes.

Handles PHP uploads in WordPress.

Tries to convert an attachment URL into a post ID.

Retrieves all category IDs.

Displays the language string for the number of comments the current post has.

Retrieves any registered editor stylesheet URLs.

Whether the site is being previewed in the Customizer.

Formerly used to escape strings before searching the DB. It was poorly documented and never worked as described.