Unverified50% confidenceFactExact time
PostgreSQL enforces unique constraint validation via B-tree indexes at transaction commit; when multiple transactions concurrently insert the same event_id, only one can commit successfully and the rest receive error code 23505.
1
Sources
50%
Confidence
Long-term
Relevance
10/18/2026
First Seen
Sources
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Related Claims
UnverifiedIn 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.69% similarUnverifiedPostgreSQL subtransactions are typically created explicitly via the SAVEPOINT command, and may also be triggered implicitly by BEGIN...EXCEPTION...END exception-handling blocks in PL/pgSQL.69% similarUnverifiedPostgreSQL treats NULL as the largest value by default, placing it at the end in ascending order and at the beginning in descending order.68% similarUnverifiedPostgreSQL's ILIKE is an operator-level explicit case-insensitive match, whereas MySQL's case-insensitive behavior depends on the collation setting of the column or connection.68% similarUnverifiedRoughly 8 to 10 significant features were reverted in PostgreSQL 19, with the exact number depending on how you count.65% similar
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