From 7a5099188eaf3e24f41ee0f49c43fba633e00a4a Mon Sep 17 00:00:00 2001
From: Fortern <blueten.ki@gmail.com>
Date: Wed, 19 Nov 2025 05:51:56 +0800
Subject: [PATCH] update

---
 PostgreSQL/common.sql   | 6 ++----
 PostgreSQL/function.sql | 6 ++++++
 PostgreSQL/user.sql     | 4 ++++
 3 files changed, 12 insertions(+), 4 deletions(-)
 create mode 100644 PostgreSQL/function.sql
 create mode 100644 PostgreSQL/user.sql

diff --git a/PostgreSQL/common.sql b/PostgreSQL/common.sql
index 7fb624f..db96442 100644
--- a/PostgreSQL/common.sql
+++ b/PostgreSQL/common.sql
@@ -1,7 +1,5 @@
--- 修改用户的密码
-alter user postgres with password '123456';
--- 查询所有用户
-select * from pg_catalog.pg_user;
+-- search_path
+SHOW search_path;
 
 -- 查询表的 COLLATION VERSION
 SELECT
diff --git a/PostgreSQL/function.sql b/PostgreSQL/function.sql
new file mode 100644
index 0000000..255a0be
--- /dev/null
+++ b/PostgreSQL/function.sql
@@ -0,0 +1,6 @@
+-- ROW 关键字生成一个元组
+SELECT ROW (1, 2, 3);
+
+-- pg_column_size函数获取存储数据需要的字节数
+SELECT pg_column_size(ROW (1,2,3)); -- 36
+SELECT pg_column_size(ROW (1::int2, 2::int2, 3::int2)); -- 30
diff --git a/PostgreSQL/user.sql b/PostgreSQL/user.sql
new file mode 100644
index 0000000..0b257c8
--- /dev/null
+++ b/PostgreSQL/user.sql
@@ -0,0 +1,4 @@
+-- 修改用户的密码
+alter user postgres with password '123456';
+-- 查询所有用户
+select * from pg_catalog.pg_user;