diff --git a/core/command/db/converttype.php b/core/command/db/converttype.php
index b4d1f0e2a1a23649baa40a7d32ba345800ff75d9..8d1560b0511b3446c6fce8bce615c14f699173f4 100644
--- a/core/command/db/converttype.php
+++ b/core/command/db/converttype.php
@@ -229,7 +229,7 @@ class ConvertType extends Command {
 
 	protected function getTables(Connection $db) {
 		$db->getConfiguration()->
-			setFilterSchemaAssetsExpression('/^'.$this->config->getSystemValue('dbtableprefix').'/');
+			setFilterSchemaAssetsExpression('/^'.$this->config->getSystemValue('dbtableprefix', 'oc_').'/');
 		return $db->getSchemaManager()->listTableNames();
 	}
 
diff --git a/lib/private/db/mdb2schemawriter.php b/lib/private/db/mdb2schemawriter.php
index aa6d578e9b5f864890d9038f4c8881f679fb06b0..a42cd86ba5434b2a7bcee6f9aa0ae60a2a02c577 100644
--- a/lib/private/db/mdb2schemawriter.php
+++ b/lib/private/db/mdb2schemawriter.php
@@ -23,7 +23,7 @@ class OC_DB_MDB2SchemaWriter {
 		$xml->addChild('charset', 'utf8');
 
 		$conn->getConfiguration()->
-			setFilterSchemaAssetsExpression('/^' . $config->getSystemValue('dbtableprefix') . '/');
+			setFilterSchemaAssetsExpression('/^' . $config->getSystemValue('dbtableprefix', 'oc_') . '/');
 
 		foreach ($conn->getSchemaManager()->listTables() as $table) {
 			self::saveTable($table, $xml->addChild('table'));
diff --git a/lib/private/db/migrator.php b/lib/private/db/migrator.php
index aecbcf418d33eda94dd55233923abc272db98a31..8ccc02e36a5c19ab63ead458f6b1dfcdb531c527 100644
--- a/lib/private/db/migrator.php
+++ b/lib/private/db/migrator.php
@@ -77,7 +77,7 @@ class Migrator {
 		$tables = $targetSchema->getTables();
 
 		$this->connection->getConfiguration()->
-			setFilterSchemaAssetsExpression('/^' . $this->config->getSystemValue('dbtableprefix') . '/');
+			setFilterSchemaAssetsExpression('/^' . $this->config->getSystemValue('dbtableprefix', 'oc_') . '/');
 		$existingTables = $this->connection->getSchemaManager()->listTableNames();
 
 		foreach ($tables as $table) {
@@ -162,7 +162,7 @@ class Migrator {
 
 	protected function getDiff(Schema $targetSchema, \Doctrine\DBAL\Connection $connection) {
 		$connection->getConfiguration()->
-			setFilterSchemaAssetsExpression('/^' . $this->config->getSystemValue('dbtableprefix') . '/');
+			setFilterSchemaAssetsExpression('/^' . $this->config->getSystemValue('dbtableprefix', 'oc_') . '/');
 		$sourceSchema = $connection->getSchemaManager()->createSchema();
 
 		// remove tables we don't know about
diff --git a/lib/private/db/pgsqltools.php b/lib/private/db/pgsqltools.php
index 3896009add42ed84df42f979792f2dbac3296ea5..f3204d4c7b656681192edcc6f9fe6a8082b8611d 100644
--- a/lib/private/db/pgsqltools.php
+++ b/lib/private/db/pgsqltools.php
@@ -34,7 +34,7 @@ class PgSqlTools {
 	public function resynchronizeDatabaseSequences(Connection $conn) {
 		$databaseName = $conn->getDatabase();
 		$conn->getConfiguration()->
-			setFilterSchemaAssetsExpression('/^' . $this->config->getSystemValue('dbtableprefix') . '/');
+			setFilterSchemaAssetsExpression('/^' . $this->config->getSystemValue('dbtableprefix', 'oc_') . '/');
 
 		foreach ($conn->getSchemaManager()->listSequences() as $sequence) {
 			$sequenceName = $sequence->getName();