Wiki / 锁

ACCESS SHARE

Conflicts with the ACCESS EXCLUSIVE lock mode only. The SELECT command acquires a lock of this mode on referenced tables. In general, any query that only reads a table and does not modify it will acquire this lock mode.

当前阅读 PG 18·选择有来源记录的版本

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此版本暂无所选语言的定义，以下显示原始英文内容。

兼容性

比较不同事务持有同一对象的锁表锁.

× 冲突模式

ACCESS EXCLUSIVE

· 兼容模式

查看完整兼容性矩阵

取得此锁模式的命令

SQL 命令	对象、阶段与条件
SELECT	Read referenced tables without a FOR locking clause. 来源
COPY … TO	Read the source table. COPY (query) TO follows the locks required by that query. 来源
LOCK TABLE … IN ACCESS SHARE MODE	Request this table mode explicitly. Omitting IN MODE defaults to ACCESS EXCLUSIVE. 来源
ALTER TABLE … NO INHERIT (parent table)	Take ACCESS SHARE on the parent while removing inheritance. The altered child separately takes ACCESS EXCLUSIVE. 来源

其他锁模式

conflicts: access-exclusive
summary: Conflicts with the ACCESS EXCLUSIVE lock mode only.

版本定义 PG 18

比较版本

完整来源事实

commands

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provenance

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来源引用

完整定义与证据 JSON

定义来源

center · PostgreSQL 18 · 10:f4e8f137bfb08a664c8288824c1e36b5143ac875;11:170e416034ec0231d9e9238f2577eeb76ca8d181;12:3f302f0ed06f69c5ebd33d4df95895323a3cbef6;13:05f6c9ec2c475fae8fdd56ae40bd01afcf70d1f2;14:fba35c7c28a567839faba867db0808564c0a66db;15:0351991b8e7c7b64382e2f30ce581a8f276590a6;16:dcc37b7099a9f3cf2c75167d8dc92e75f96bc1fa;17:163288afd32a448244c8df75b3c33181aadd7f20;18:753057e340da8f22e57c9a409ea7a235fd6a46bd;19:b73d13c32c834a2c8e1c60cb92f79530376cedf1;20:2c10c2ce4d7bcd57543a49ab402af02a39724e0a

正文语言: en · 10:f4e8f137bfb08a664c8288824c1e36b5143ac875;11:170e416034ec0231d9e9238f2577eeb76ca8d181;12:3f302f0ed06f69c5ebd33d4df95895323a3cbef6;13:05f6c9ec2c475fae8fdd56ae40bd01afcf70d1f2;14:fba35c7c28a567839faba867db0808564c0a66db;15:0351991b8e7c7b64382e2f30ce581a8f276590a6;16:dcc37b7099a9f3cf2c75167d8dc92e75f96bc1fa;17:163288afd32a448244c8df75b3c33181aadd7f20;18:753057e340da8f22e57c9a409ea7a235fd6a46bd;19:b73d13c32c834a2c8e1c60cb92f79530376cedf1;20:2c10c2ce4d7bcd57543a49ab402af02a39724e0a