diff --git a/PostgreSQL/settings.sql b/PostgreSQL/settings.sql
new file mode 100644
index 0000000..6828b39
--- /dev/null
+++ b/PostgreSQL/settings.sql
@@ -0,0 +1,2 @@
+-- 查询 effective_cache_size
+select * from pg_settings where name like 'effective_cache_size';
\ No newline at end of file