Backport subset of #4179, re-established Oracle compatibility for LDAP

Conflicts:
	apps/user_ldap/lib/access.php

apps/user_ldap/lib/access.php

@@ -607,7 +607,7 @@ class Access extends LDAPUtility implements user\IUserTools {
 
 		$sqlAdjustment = '';
 		$dbType = \OCP\Config::getSystemValue('dbtype');
-		if($dbType === 'mysql') {
+		if($dbType === 'mysql' || $dbType == 'oci') {
 			$sqlAdjustment = 'FROM DUAL';
 		}
 

apps/user_ldap/lib/helper.php

@@ -159,7 +159,8 @@ class Helper {
 			return false;
 		}
 
-		if(strpos(\OCP\Config::getSystemValue('dbtype'), 'sqlite') !== false) {
+		$dbtype = \OCP\Config::getSystemValue('dbtype');
+		if(strpos($dbtype, 'sqlite') !== false || $dbtype === 'oci') {
 			$query = \OCP\DB::prepare('DELETE FROM '.$table);
 		} else {
 			$query = \OCP\DB::prepare('TRUNCATE '.$table);