> 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/13/server-programming/extending-sql/procedural-language-functions.md).

# 37.8. Procedural Language Functions

PostgreSQL 允許使用者定義的函數用 SQL 和 C 之外的其他語言撰寫。這些其他的程式語言通常稱為程序語言（PL）。程序語言並沒有內建在 PostgreSQL 伺服器中的。它們由可外掛模組提供。有關更多資訊，請參閱第 41 章和後續章節。


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