PostgreSQL 15 ← 14
← 目录图谱 / pg_shdepend
SYSTEM CATALOG · 系统目录
pg_shdepend
The catalog pg_shdepend records the dependency relationships between database objects and shared objects, such as roles. This information allows PostgreSQL to ensure that those objects are unreferenced before attempting to delete them. See also pg_depend, which performs a similar function for dependencies involving objects within a single database. Unlike most system catalogs, pg_shdepend is shared across all databases of a cluster: there is only one copy of pg_shdepend per cluster, not one per database.
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_shdependPostgreSQL 19 beta 3 是预发布快照，结构在正式发布前仍可能变化。
| 字段 / COLUMN | 类型 / TYPE | 说明 / DESCRIPTION |
|---|---|---|
dbid |
oidNOT NULL |
The OID of the database the dependent object is in, or zero for a shared object引用：pg_database.oid |
classid |
oidNOT NULL |
The OID of the system catalog the dependent object is in引用：pg_class.oid |
objid |
oidNOT NULL |
The OID of the specific dependent object引用：any OID column |
objsubid |
integerNOT 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 |
oidNOT NULL |
The OID of the system catalog the referenced object is in (must be a shared catalog)引用：pg_class.oid |
refobjid |
oidNOT NULL |
The OID of the specific referenced object引用：any OID column |
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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
dbid |
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classid |
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objid |
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objsubid |
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refclassid |
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refobjid |
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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 14 ← 13
比较任意两个版本
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。