wp-admin/includes/upgrade.php:1535Remove old options from the database.
function upgrade_230_options_table() { global $wpdb; $old_options_fields = array( 'option_can_override', 'option_type', 'option_width', 'option_height', 'option_description', 'option_admin_level' ); $wpdb->hide_errors(); foreach ( $old_options_fields as $old ) { $wpdb->query( "ALTER TABLE $wpdb->options DROP $old" ); } $wpdb->show_errors();}Introduced in 2.3.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-admin/includes/upgrade.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.