Unverified50% confidenceFactExact time
In PostgreSQL, first creating a unique index and then attaching it as a constraint with ADD CONSTRAINT ... UNIQUE USING INDEX splits index construction and constraint registration into two steps, allowing the uniqueness guarantee to take effect without blocking writes for a long time.
1
Sources
50%
Confidence
Long-term
Relevance
10/18/2026
First Seen
Sources
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