Postgres MERGE RETURNING: Old and New Values (2026)
July 2, 2026
Postgres 18 lets MERGE RETURNING return old and new row values in one query. See merge_action(), the xmax alternative, and verified Node.js/TypeScript code.
Postgres 18 lets MERGE RETURNING return old and new row values in one query. See merge_action(), the xmax alternative, and verified Node.js/TypeScript code.