github/gh-ost on Hacker News

…always online migrations. iirc githhub's migration tool was open source right? Edit: yes it was https://github.com/github/gh-ost

comment by dvtkrlbs · 2025-03-01 · in EdgeDB is now Gel and Postgres is the future

…large relational databases is online schema change tools like https://github.com/shayonj/pg-osc and https://github.com/github/gh-ost (the latter developed for GitHub’s monolith). It’s just too difficult to model what migrations will cause…

comment by semiquaver · 2024-02-18 · in My notes on Gitlab's Postgres schema design (2022)

This github issue is often linked when this topic is discussed: https://github.com/github/gh-ost/issues/331 > Personally, it took me quite a few years to make up my mind about whether foreign keys are good or evil, and for the past 3 years…

comment by lrobinovitch · 2023-12-21 · in Do you really need foreign keys?

Sounds like it's basically explained in the gh-ost readme https://github.com/github/gh-ost#how I think it amounts to "use views to decouple access to the table with a fixed interface" and "use triggers for migrating data between tables"

comment by nijave · 2023-10-09 · in We migrated to SQL. Our biggest learning? Don't use Prisma

With foreign keys, I can't use https://github.com/github/gh-ost for zero downtime migrations. Instant deal breaker, because schema changes are inevitable given business evolution.

comment by francislavoie · 2023-10-09 · in We migrated to SQL. Our biggest learning? Don't use Prisma

…version control benefits of Dolt and keep an existing MySQL or MariaDB database. #. github/gh-ost: https://github.com/github/gh-ost : > Instead, gh-ost uses the binary log stream to capture table changes, and asynchronously applies them…

comment by westurner · 2023-08-09 · in SQLedge: Replicate Postgres to SQLite on the Edge

check out gh-ost migrations: https://github.com/github/gh-ost

comment by newtom · 2023-05-23 · in Is 20M of rows still a valid soft limit of MySQL table in 2023?

Gh-ost is the new hotness. Simple to use and lots of great features: https://github.com/github/gh-ost

comment by ericbarrett · 2023-04-17 · in Ask HN: Is PostgreSQL better than MySQL?

Use SQL without foreign keys for best performance [0]. [0]: https://github.com/github/gh-ost/issues/331#issuecomment-266...

comment by ffhhj · 2022-10-18 · in NoSQL or SQL – how you make the choice?

…on large tables with billions of records. They make online schema changes impossible. More details: https://github.com/github/gh-ost/issues/331#issuecomment-266...

comment by golondon · 2022-09-06 · in Ask HN: Do you use foreign keys in relational databases?

…I had the impression you have to setup a normal non-RDS replica attached to your RDS master? [1] https://github.com/github/gh-ost/blob/master/doc/rds.md

comment by darkwater · 2022-05-05 · in Zero downtime migrations

…is probably the state of the art, and uses the binary log stream to replicate the data. [1] https://github.com/github/gh-ost

comment by antoncohen · 2022-05-05 · in Zero downtime migrations

…to every company sooner or later, but if a company the size of GitHub can still do without ( https://github.com/github/gh-ost/issues/331#issuecomment-266... ) it does become a little bit of a "you do not have google problems" type…

comment by WJW · 2022-04-19 · in How we upgraded our 4TB Postgres database

…likely have some system process that does this instead of a simple `DELETE FROM` which cascades. 1. https://github.com/github/gh-ost/issues/331#issuecomment-266...

comment by anonfunction · 2022-04-15 · in We lost 54k GitHub stars

…matter that it takes forver? Nope because it doesn't lock tables. And even if you do have triggers https://github.com/github/gh-ost you can still do it.

comment by Spivak · 2022-01-13 · in In MySQL, use “utf8mb4” instead of “utf8” (2016)

For MySQL we use github's tool gh-ost https://github.com/github/gh-ost There is a few tech restrictions, but if your database meets that it works great. I migrated huge tables with absolutely no impact on production

comment by boudin · 2022-01-07 · in Zero-downtime schema migrations in Postgres using Reshape

…changes in Vitess. Links: - https://www.percona.com/doc/percona-toolkit/3.0/pt-online-sc... - https://github.com/github/gh-ost - Past HN discussion: https://news.ycombinator.com/item?id=16982986 - https://dev.mysql.com/doc/refman/8.0/en/inn…

comment by shlomi-noach · 2021-12-06 · in Leaving MySQL

…some time in documenting how it works. Similarly, I co-designed and was the main author for gh-ost, https://github.com/github/gh-ost , as part of the database infrastructure team at GitHub. We developed gh-ost because the existing schema…

comment by shlomi-noach · 2021-11-17 · in PlanetScale is now generally available

…model where I don't pay for e.g. RDS allocation. And I say that as a really big PostgreSQL fan. [1] https://github.com/github/gh-ost

comment by aseipp · 2021-11-17 · in PlanetScale is now generally available

…Disclosure: I'm the author of Skeema, but have not worked for or with GitHub in any capacity. [1] https://github.com/github/gh-ost [2] https://github.blog/2020-02-14-automating-mysql-schema-migra... [3]…

comment by evanelias · 2021-03-12 · in GitHub was down

…migrations cause downtime [1]: https://stackoverflow.com/questions/805363/how-do-i-rename-a... [2]: https://github.com/github/gh-ost

comment by srcreigh · 2021-02-19 · in Many small queries are efficient in SQLite

…don't have triggers/foreign keys on a given MySQL table, Gh-ost¹ solves the DDL locking issues. ¹= https://github.com/github/gh-ost

comment by pizza234 · 2021-02-12 · in AWS Babelfish: The Elephant in the PostgreSQL Room?

…DB management tooling ( https://github.com/openark/orchestrator ) and online migration tooling ( https://github.com/github/gh-ost )

comment by t3rabytes · 2021-01-25 · in Improving how we deploy GitHub

…obviously it is workable, but I think every big MySQL org ends up with a tool/workflow like gh-ost: https://github.com/github/gh-ost which have their own set of challenges, like not playing well with foreign keys.

comment by ReidZB · 2020-04-07 · in A humble guide to database schema design

Check out https://github.com/github/gh-ost

comment by jlisam13 · 2020-03-27 · in Ask HN: Database migration on production without downtime

…able to do them on a replica and then run tests is cool. If you use MySQL look into Githubs tool https://github.com/github/gh-ost

comment by gigatexal · 2018-12-21 · in Ask HN: What database version management tools do you use?

…have to worry about updating foreign keys. Here are some of Github's reasons for not using them: https://github.com/github/gh-ost/issues/331 I think this is pretty normal for heavy MySQL users, honestly. When I was at Eventbrite we didn't…

comment by sciurus · 2018-10-23 · in Django zero-downtime migrations for Postgres that respect database locks

…I historically found more tools for online schema changes in the mysql sphere, such as gh-ost ( https://github.com/github/gh-ost )

comment by etaioinshrdlu · 2018-10-23 · in Django zero-downtime migrations for Postgres that respect database locks

Yeah. See https://github.com/github/gh-ost/issues/507#issuecomment-338... on how to do it in a performant way.

comment by zmoazeni · 2018-05-03 · in GitHub's online schema migration for MySQL

…[4] https://dev.mysql.com/doc/refman/5.6/en/innodb-create-index-... [5] https://github.com/github/gh-ost/issues/507#issuecomment-338...

comment by zmoazeni · 2018-05-03 · in GitHub's online schema migration for MySQL

shlomi-noach linked to https://github.com/github/gh-ost/issues/331 in another comment. That goes into some of the reasons to avoid foreign keys. At a past job where we had a complex MySQL setup, I set up a slack autoresponse to post "Just…

comment by sciurus · 2018-05-03 · in GitHub's online schema migration for MySQL

…(the foreign key constraint has a unique name in a schema) -- but it should work. See discussion in https://github.com/github/gh-ost/issues/507 It is true that it is not on our roadmap to implement FK support for gh-ost (see…

comment by shlomi-noach · 2018-05-03 · in GitHub's online schema migration for MySQL

Yes, https://github.com/github/gh-ost/search?utf8=%E2%9C%93&q=go-...

comment by tejasmanohar · 2018-05-03 · in GitHub's online schema migration for MySQL

…- FB's OSC ( https://www.facebook.com/notes/mysql-at-facebook/online-sche... ) - GH's gh-ost ( https://github.com/github/gh-ost )

comment by michaeldejong · 2018-03-24 · in Managing database schema changes without downtime

…tools have "given up" on foreign key constraints. [0] http://code.openark.org/forge/openark-kit [1] https://github.com/github/gh-ost

comment by michaeldejong · 2018-03-24 · in Managing database schema changes without downtime

…ttps://github.com/yoshinorim/mha4mysql-manager ), ProxySQL ( http://www.proxysql.com/ ), and gh-ost ( https://github.com/github/gh-ost ), along knowledge and best practices shared by those organization.

comment by antoncohen · 2017-12-06 · in PostgreSQL HA cluster failure: a post-mortem

Another tool in this category is gh-ost by github: https://github.com/github/gh-ost Its main advantage seems to be that it doesn't require triggers on the original table (it works by subscribing to the replication log), thus not making…

comment by perlgeek · 2017-02-02 · in Online migrations at scale

…docs[0]: Amazon RDS and Google Cloud SQL are probably not supported (due to SUPER requirement) [0]: https://github.com/github/gh-ost/blob/master/doc/requirement...

comment by jzelinskie · 2016-08-02 · in Gh-ost: GitHub's online schema migration tool for MySQL