The perils of UUID primary keys in SQLite
This article explains the performance degradation caused by using random UUIDs as primary keys in SQLite databases. It demonstrates that random UUIDs cause excessive B-tree re-balancing and paging compared to sequential integer keys.
Why it matters
Understanding database indexing is critical for software engineers to optimize application performance and scalability.
It's common to use random UUIDs as a primary key in databases. One of the known downsides of random UUIDs is that their unordered nature (UUID4) can cause a lot of extra paging for the clustered index because you are inserting rows randomly into the Btree and having to re-balance it. This post tries to help us develop a more visceral understanding of the performance cost of all that extra paging.
The content is purely technical and objective, focusing on database performance metrics.
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