nextcloud/apps/contacts/appinfo/update.php

<?php

$installedVersion=OCP\Config::getAppValue('contacts', 'installed_version');
if (version_compare($installedVersion, '0.2.3', '<')) {
	// First set all address books in-active.
	$stmt = OCP\DB::prepare( 'UPDATE *PREFIX*contacts_addressbooks SET active=0' );
	$result = $stmt->execute(array());
	
	// Then get all the active address books.
	$stmt = OCP\DB::prepare( 'SELECT userid,configvalue FROM *PREFIX*preferences WHERE appid=\'contacts\' AND configkey=\'openaddressbooks\'' );
	$result = $stmt->execute(array());
	
	// Prepare statement for updating the new 'active' field.
	$stmt = OCP\DB::prepare( 'UPDATE *PREFIX*contacts_addressbooks SET active=? WHERE id=? AND userid=?' );
	while( $row = $result->fetchRow()) {
		$ids = explode(';', $row['configvalue']);
		foreach($ids as $id) {
			$r = $stmt->execute(array(1, $id, $row['userid']));
		}
	}
	
	// Remove the old preferences.
	$stmt = OCP\DB::prepare( 'DELETE FROM *PREFIX*preferences WHERE appid=\'contacts\' AND configkey=\'openaddressbooks\'' );
	$result = $stmt->execute(array());
}