On Mon, Sep 8, 2025 at 4:01 AM Vivek Gadge <vvkgadg...@gmail.com> wrote: > > Hi Team, > > We are currently experiencing performance issues related to partition > scanning on a heavily used table in our PostgreSQL v17.6 database. > > The table is partitioned monthly (e.g., transactions_jan25, > transactions_feb25, …, transactions_sept25). We’ve observed that PostgreSQL > scans these partitions in the order they were attached (January through > September). > > This behavior is leading to inefficient query performance when accessing > recent data (e.g., August or September), as older partitions are being > scanned first — adding unnecessary overhead. Since PostgreSQL does not > provide a built-in setting to prioritize scanning partitions in descending > order, we’re exploring ways to address this. > > Could you please advise on: > > How to optimize partition scanning so that recent partitions are scanned > first, and > > Any recommended best practices or workarounds to improve performance in such > scenarios. > > Looking forward to your guidance. > > Thank you >
Can you please describe how the query performance is affected because of the order in which partitions are scanned? -- Best Wishes, Ashutosh Bapat
