1 files changed, 7 insertions, 4 deletions
diff --git a/apps/oauth2/lib/Migration/Version010402Date20190107124745.php b/apps/oauth2/lib/Migration/Version010402Date20190107124745.php
index ff9a628712a..b80e3a9575f 100644
--- a/apps/oauth2/lib/Migration/Version010402Date20190107124745.php
+++ b/apps/oauth2/lib/Migration/Version010402Date20190107124745.php
@@ -42,9 +42,12 @@ class Version010402Date20190107124745 extends SimpleMigrationStep {
 		/** @var ISchemaWrapper $schema */
 		$schema = $schemaClosure();
 
-		$table = $schema->getTable('oauth2_clients');
-		$table->dropIndex('oauth2_client_id_idx');
-		$table->addUniqueIndex(['client_identifier'], 'oauth2_client_id_idx');
-		return $schema;
+		// During an ownCloud migration, the client_identifier column identifier might not exist yet.
+		if ($schema->getTable('oauth2_clients')->hasColumn('client_identifier')) {
+			$table = $schema->getTable('oauth2_clients');
+			$table->dropIndex('oauth2_client_id_idx');
+			$table->addUniqueIndex(['client_identifier'], 'oauth2_client_id_idx');
+			return $schema;
+		}
 	}
 }