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This is missing one huge point of the [uber engineer post](https://eng.uber.com/mysql-migration/).

They did not switch from a postgres instance to put all their data in a mysql instance. They switched from a single postgres instance to shard their data across many mysql instances. This an entire reworking of the architecture that is completely ignored in this powerpoint.

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Honestly I think Uber switching was more of a business decision as their employees had trouble figuring out how to properly use Postgres. Instagram definitely has different data needs, but is probably much bigger than Uber wrt data. They use Postgres successfully via Django no less!

https://engineering.instagram.com/sharding-ids-at-instagram-...

As someone who participated in this transition, I don't think that was a part of it. The new database layer took quite a bit of instruction to use properly as well, and there were plenty of people misusing it.

> switched from a single postgres instance

did you even read the post?

There's replication, but I mean that all the data is in one pg instance, whereas there isn't a single mysql instance with all the data.

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