> 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/14/server-programming/event-triggers.md).

# 39. Event Triggers (事件觸發)

為了補充[第 38 章](/14/server-programming/triggers.md)中討論的觸發(Trigger)機制，PostgreSQL 還提供了事件觸發。與附加到單個資料表只能用於 DML 事件的一般觸發器不同，事件觸發器是特定資料庫的全域觸發器，能夠在 DDL 事件發生時觸發。

與一般觸發器一樣，事件觸發器可以用任何包含事件觸發器所支援的程序語言撰寫，也可以用 C 語言撰寫，但不能使用普通的 SQL。


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