Does a Postgres UNIQUE constraint imply an index?

Question

When adding a unique constraint to a Postgres table does that imply that an index has also been added to that table?

Meaning, if I add a UNIQUE constraint on a text column, does that text column now have an index or does an index have to be added separately?

Erwin Brandstetter · Accepted Answer · 2021-04-06 00:01:34Z

13

Yes.
UNIQUE constraints are implemented using a unique B-tree index in Postgres.

See:

answered Apr 15, 2015 at 16:17

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