> 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/15/appendixes/additional-supplied-modules/old_snapshot.md).

# F.24. old\_snapshot

## F.24. old\_snapshot

[F.24.1. 函式](#id-1.11.7.33.4)

`old_snapshot` 模組可檢視伺服器用來實作 [old\_snapshot\_threshold](/15/server-administration/server-configuration/resource-consumption.md#GUC-OLD-SNAPSHOT-THRESHOLD) 的狀態。

### F.24.1. 函式

`pg_old_snapshot_time_mapping(array_offset OUT int4, end_timestamp OUT timestamptz, newest_xmin OUT xid) returns setof record`

傳回伺服器時間戳記至 XID 對應中的所有項目。每個項目代表相應分鐘內所取得任何快照的最新 xmin。

***

原文：[PostgreSQL 15.19 Documentation](https://www.postgresql.org/docs/15/old-snapshot.html)


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