48 lines
1.4 KiB
Markdown
48 lines
1.4 KiB
Markdown
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# 4. UUIDs for primary keys
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Date: 2024-05-31
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## Status
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Proposed
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## Context
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We need primary keys in our database.
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I've used integers and UUIDs for this in different contexts. Ultimately, we have
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to decide on which one to use.
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## Decision
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We're going to use UUIDs for our primary keys.
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The primary motivation here is that it will give us the ability to generate IDs
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before inserting records, and it lets us expose the IDs more easily. Instead of
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either leaking information (count of users, etc.) or having a secondary mapping
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for URLs, we can easily use the ID in a URL to map to a record for lookup.
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## Consequences
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There are some drawbacks:
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- We lose some type safety, becasue SQLite only supports text/blob types and
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it's been a blocker trying to implement custom sql types in Diesel, so this is
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going to be done by converting to strings and operating on these IDs as
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strings.
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- They take up more space
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However, we get these benefits:
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- We can expose primary keys without leaking information. This makes it so we
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do not need secondary IDs (and associated indexes) for looking up specific
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records and putting them in URLs, where if we used integers we'd need that or
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we would have to accept exposing the number of records we have.
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- IDs are unique across tables, so they should give us the ability to find a
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particular row even if we don't know the table. This also means we could link
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events, like edit events, to any table via UUID.
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