diff --git a/phpBB/phpbb/db/doctrine/table_helper.php b/phpBB/phpbb/db/doctrine/table_helper.php
index 70ac39078f..ec5c2040e8 100644
--- a/phpBB/phpbb/db/doctrine/table_helper.php
+++ b/phpBB/phpbb/db/doctrine/table_helper.php
@@ -214,7 +214,7 @@ class table_helper
 		];
 
 		// Add table prefix to additional tables
-		if (!empty($table_prefix && !empty($additional_tables)))
+		if (!empty($table_prefix) && !empty($additional_tables))
 		{
 			foreach ($additional_tables as $key => $value)
 			{
diff --git a/tests/dbal/migrator_test.php b/tests/dbal/migrator_test.php
index ac502f1816..454c05b5eb 100644
--- a/tests/dbal/migrator_test.php
+++ b/tests/dbal/migrator_test.php
@@ -491,7 +491,7 @@ class phpbb_dbal_migrator_test extends phpbb_database_test_case
 			$index_prefix = $short_table_names[$table_name] . '_';
 			foreach ($key_names as $key_name)
 			{
-				$this->assertFalse(strpos($key_name, $index_prefix), "$key_name does not contain $index_prefix");
+				$this->assertEquals(0, strpos($key_name, $index_prefix), "$key_name does not contain $index_prefix");
 			}
 		}
 	}