SYSTEM CATALOG · 系统目录

pg_policy

The catalog pg_policy stores row-level security policies for tables. A policy includes the kind of command that it applies to (possibly all commands), the roles that it applies to, the expression to be added as a security-barrier qualification to queries that include the table, and the expression to be added as a WITH CHECK option for queries that attempt to add new records to the table.

首次收录 PG 9.5最近收录 PG 19当前字段 8

9.0 9.1 9.2 9.3 9.4 9.5 9.6 10 11 12 13 14 15 16 17 18 19^β3

已与 PostgreSQL 18.6 实例逐字段核对 · 原始实测记录 ↗

字段结构 PostgreSQL 18

pg_policy

字段 / COLUMN	类型 / TYPE	说明 / DESCRIPTION
`oid`	`oid`NOT NULL	Row identifier
`polname`	`name`NOT NULL	The name of the policy
`polrelid`	`oid`NOT NULL	The table to which the policy applies引用：`pg_class.oid`
`polcmd`	`"char"`NOT NULL文档原写法：`char`	The command type to which the policy is applied: r for SELECT, a for INSERT, w for UPDATE, d for DELETE, or * for all
`polpermissive`	`boolean`NOT NULL文档原写法：`bool`	Is the policy permissive or restrictive?
`polroles`	`oid[]`NOT NULL	The roles to which the policy is applied; zero means PUBLIC (and normally appears alone in the array)引用：`pg_authid.oid`
`polqual`	`pg_node_tree`	The expression tree to be added to the security barrier qualifications for queries that use the table
`polwithcheck`	`pg_node_tree`	The expression tree to be added to the WITH CHECK qualifications for queries that attempt to add rows to the table

标记“隐式列”的字段不包含在 SELECT * 中；部分早期统计视图由同版本源码补全，额外来源会显示在字段说明中。

通用系统列 6

PostgreSQL 提供的系统属性，通常不在 SELECT * 中展开。单独保留，不与普通字段混算。

字段	类型	attnum
`tableoid`	`oid`	-6
`cmax`	`cid`	-5
`xmax`	`xid`	-4
`cmin`	`cid`	-3
`xmin`	`xid`	-2
`ctid`	`tid`	-1

字段演化矩阵

悬停查看字段类型

存在新增 / 类型或属性变化移除

字段 / COLUMN	9.0	9.1	9.2	9.3	9.4	9.5	9.6
`oid`	–	–	–	–	–
`polname`	–	–	–	–	–
`polrelid`	–	–	–	–	–
`polcmd`	–	–	–	–	–
`polroles`	–	–	–	–	–
`polqual`	–	–	–	–	–
`polwithcheck`	–	–	–	–	–
`polpermissive`	–	–	–	–	–	–	–

9.0 是收录基线；基线中已存在的字段不标记为新增。矩阵按字段名称对齐，重命名显示为旧字段移除与新字段新增。

演化时间线

相邻大版本的变化

PostgreSQL 14 ← 13

1 处字段说明更新目录说明更新

PostgreSQL 13 ← 12

1 处字段说明更新

PostgreSQL 12 ← 11

~ oid: 隐式列 → 常规列~ polroles: not_null: false → true1 处字段说明更新

PostgreSQL 10 ← 9.6

+ polpermissive

PostgreSQL 9.5 ← 9.4新增目录

+ oid+ polname+ polrelid+ polcmd+ polroles+ polqual+ polwithcheck

比较任意两个版本

起始版本 / FROM目标版本 / TO包含描述更新

选择两个版本，查看字段的新增、移除与类型变化。交互比较需要 JavaScript；演化时间线可直接阅读。