You could also COUNT on a query/filter to see if it exists by row count, then INSERT or UPDATE based on if there is an existing item for that filter/query. That is still two calls and can be safer, it can also be done in a transaction.

Lots of app level code in ORMs that use ADD/EDIT or CREATE/UPDATE actions can encapsulate this by just a SET, which counts the rows and then if zero INSERTS, if > 0 UPDATE.