UPDATE OR INSERT INTO <table or view> [(<column_list>)]
VALUES (<value_list>)
[MATCHING <column_list>]
[RETURNING <column_list> [INTO <variable_list>]]

Examples:
1. UPDATE OR INSERT INTO T1 (F1, F2) VALUES (:F1, :F2);
2. UPDATE OR INSERT INTO EMPLOYEE (ID, NAME) VALUES (:ID, :NAME) RETURNING ID;
3. UPDATE OR INSERT INTO T1 (F1, F2) VALUES (:F1, :F2) MATCHING (F1);