# multiple database performance

**URL:** <https://forums.percona.com/t/multiple-database-performance/743>\
**Category:** Other MySQL® Questions\
**Created:** [May 2, 2008, 2:22pm UTC](https://forums.percona.com/t/multiple-database-performance/743 "2008-05-02T14:22:00Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![rlangham](https://avatars.discourse-cdn.com/v4/letter/r/ecccb3/32.png) [@rlangham](https://forums.percona.com/u/rlangham)\
**Post date:** [May 2, 2008, 2:22pm UTC](https://forums.percona.com/t/multiple-database-performance/743/1 "2008-05-02T14:22:00Z")

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Generally, how does performance of queries across multiple databases compare to a query on many tables in the same database? We are considering creating a separate database with its own tables that logically should be separate, but at times we will need to run a query (with joins) across the two databases. Is there a big performance hit for this?

Thanks,  
Ron