> For the complete documentation index, see [llms.txt](https://docs.postgresql.tw/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.postgresql.tw/appendixes/appendix-obsolete/default-roles.md).

# O.2. 預設角色已改名為預先定義角色 \#

PostgreSQL 13 及更早版本使用「預設角色」（Default Roles）一詞。然而，這些角色實際上無法變更，且會在系統初始化時隨系統一併安裝，因此較恰當的名稱是「預先定義角色」（Predefined Roles）。 關於預先定義角色的現行文件請參閱[第 21.5 節](/server-administration/user-manag/predefined-roles.md)；關於此變更的詳細資訊請參閱 [PostgreSQL 14 的發行說明](/appendixes/release/release-prior.md)。

***

原文：[PostgreSQL 18.6 Documentation](https://www.postgresql.org/docs/18/default-roles.html)（原文版本：18.6；核對日期：2026-09-06）


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