mariadb-replace

MariaDB-specific syntax and behavior for REPLACE — why REPLACE is DELETE-then-INSERT (not an upsert/UPDATE), when it triggers (PRIMARY/UNIQUE conflicts only), its data-loss footguns (unlisted columns reset to DEFAULT, AUTO_INCREMENT burned, ON DELETE cascades and DELETE+INSERT triggers fired), the INSERT … ON DUPLICATE KEY UPDATE alternative, REPLACE … RETURNING, the SET and SELECT forms, PARTITION targeting, and the INSERT+DELETE privilege requirement. Use when writing, generating, or reviewing REPLACE statements, or when an upsert is being considered.