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by orf 1688 days ago
Why would you use a btree for them? Wouldn’t a hash index be ideal?
2 comments
masklinn 1688 days ago
> Why would you use a btree for them?

1. because PRIMARY KEY is its own constraint, and the underlying index is not under you control

2. because PRIMARY KEY further restricts UNIQUE, and as of postgres 14 "only B-tree indexes can be declared unique"

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tomnipotent 1688 days ago
Some databases don't give you a choice, and your table data is actually stored in a clustered index sorted by primary key. This means random inserts when using a UUID (without embedded time), and more page splitting.
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