> 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/color/color-when.md).

# N.1. 何時使用色彩 \#

若要使用彩色輸出，請依下列方式設定環境變數 `PG_COLOR`：

1. 值為 `always` 時，使用色彩。
2. 值為 `auto`，且標準錯誤串流連接至終端機裝置時，使用色彩。
3. 其他情況不使用色彩。

***

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


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