1. upsert - Noun
2. upsert - Verb
upsert (third-person singular simple present upserts, present participle upserting, simple past and past participle upserted)
(databases, transitive) To insert rows into a database table if they do not already exist, or update them if they do.
upsert (plural upserts)
(databases) An operation that inserts rows into a database table if they do not already exist, or updates them if they do.
Synonym: (SQL standard) merge