SYSTEM CATALOG · 系统目录

pg_depend

The catalog pg_depend records the dependency relationships between database objects. This information allows DROP commands to find which other objects must be dropped by DROP CASCADE or prevent dropping in the DROP RESTRICT case. See also pg_shdepend, which performs a similar function for dependencies involving objects that are shared across a database cluster.

首次收录 PG 9.0最近收录 PG 19当前字段 7

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_depend

字段 / COLUMN	类型 / TYPE	说明 / DESCRIPTION
`classid`	`oid`NOT NULL	The OID of the system catalog the dependent object is in引用：`pg_class.oid`
`objid`	`oid`NOT NULL	The OID of the specific dependent object引用：`any OID column`
`objsubid`	`integer`NOT NULL文档原写法：`int4`	For a table column, this is the column number (the objid and classid refer to the table itself). For all other object types, this column is zero.
`refclassid`	`oid`NOT NULL	The OID of the system catalog the referenced object is in引用：`pg_class.oid`
`refobjid`	`oid`NOT NULL	The OID of the specific referenced object引用：`any OID column`
`refobjsubid`	`integer`NOT NULL文档原写法：`int4`	For a table column, this is the column number (the refobjid and refclassid refer to the table itself). For all other object types, this column is zero.
`deptype`	`"char"`NOT NULL文档原写法：`char`	A code defining the specific semantics of this dependency relationship; see text

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	10	11	12	13	14	15	16	17	18	19
`classid`
`objid`
`objsubid`
`refclassid`
`refobjid`
`refobjsubid`
`deptype`

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 15 ← 14

2 处字段说明更新

PostgreSQL 14 ← 13

2 处字段说明更新

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。