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It also works fine with Aurora, as long as you have binary logging enabled.
by earless1 4y ago
It also works fine with Aurora, as long as you have binary logging enabled.
- evanelias 4y agoThat's true. However, if you don't already have any "traditional" (binlog-based) replicas on Aurora, you might not even need gh-ost or pt-osc in the first place -- at least for many common ALTER operations. Aurora supports physical replication at the storage level, which means you can use MySQL online DDL (ALGORITHM=INPLACE, LOCK=NONE) without having to worry about replication lag. Recent blog post with findings from Percona: https://www.percona.com/blog/zero-impact-on-index-creation-with-amazon-aurora-3/ https://www.percona.com/blog/zero-impact-on-index-creation-w... Caveats: * This is safe on Aurora 3 due to MySQL 8's atomic DDL support. On previous versions, there may be crash-safety risks, which make external tools safer for altering very large tables. * External OSC tools can provide other advantages, such as throttling, safer to cancel, ability to time the final table switchover, ability to rollback (pt-osc supports "reverse" triggers), etc. * Some forms of ALTER TABLE don't support online DDL, and for those you'd still need an external OSC tool like gh-ost or pt-osc, but it's less common.