update

2025-11-19 05:51:56 +08:00
parent 7b1465fc4e
commit 7a5099188e
3 changed files with 12 additions and 4 deletions
--- a/PostgreSQL/function.sql
+++ 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