diff --git a/phpBB/docs/sphinx.sample.conf b/phpBB/docs/sphinx.sample.conf
index cb19d011e3..5da4ea78df 100644
--- a/phpBB/docs/sphinx.sample.conf
+++ b/phpBB/docs/sphinx.sample.conf
@@ -40,6 +40,7 @@ source source_phpbb_{SPHINX_ID}_main
 }
 source source_phpbb_{SPHINX_ID}_delta : source_phpbb_{SPHINX_ID}_main
 {
+	sql_query_pre =
 	sql_query_range =
 	sql_range_step =
 	sql_query = SELECT\