Lots of databases have MERGE but it&#x27;s different from the typical UPDATE OR INSERT logic in terms of use cases, table requirements and concurrency control.<p>Here&#x27;s a great post from Postgres team showing why they didn&#x27;t just implement merge themselves:<p><a href="http:&#x2F;&#x2F;www.postgresql.org&#x2F;message-id&#x2F;CAM3SWZRP0c3g6+aJ=YYDGYAcTZg0xA8-1_FCVo5Xm7hrEL34kw@mail.gmail.com" rel="nofollow">http:&#x2F;&#x2F;www.postgresql.org&#x2F;message-id&#x2F;CAM3SWZRP0c3g6+aJ=YYDGY...</a>