postgres-syntax-upsert-merge

To perform an UPSERT in PostgreSQL, use the INSERT ... ON CONFLICT statement to execute idempotent inserts and updates. This syntax automatically handles unique constraint violations by updating the existing row instead of throwing an error.

The MERGE statement in PostgreSQL is used for complex data synchronization tasks, allowing you to perform atomic inserts, updates, and deletes with conflict resolution. It is ideal for handling various conflict scenarios during database migrations.

Yes, using the MERGE syntax and ON CONFLICT clause requires PostgreSQL 9.5 or later. You need knowledge of these specific features to execute atomic data operations and implement robust migration strategies correctly.

The best way to synchronize data atomically is by using the PostgreSQL MERGE statement. It manages complex data synchronization from a source to a target table, handling conditional updates and inserts within a single transaction.

Use ON CONFLICT for simpler idempotent inserts and updates based on unique constraints. Use MERGE for more complex data synchronization and migration strategies requiring conditional logic across multiple matched and unmatched scenarios.