Re: Merge statement

George Neuner <[email protected]> Tue, 24 Sep 2019 12:31:53 -0400
Newsgroups gmane.comp.db.postgresql.admin
Message-ID <[email protected]>
On Mon, 23 Sep 2019 15:48:06 +0000 (UTC), Pepe TD Vo <[email protected]> 
wrote:

 >Yes, I heard  MERGE is not a command in Postgres but the others said
 >merge statement added stored procedures in version 11
 >
 >I upgraded my postgresql from 10.6 to 11.1. in AWS, still not work.
 >thank you,
 >Bach-Nga

You misunderstood.

Postrgesql added stored procedures in version 11.  Unlike stored 
/functions/ (which PG has had forever), stored procedures allow 
transactions within their code. This is similar to the stored procedures 
in Oracle and it helps with Oracle -> Postgresql conversions.

However, Postgresql does NOT and never did have a MERGE command. The 
"documentation" page you discovered was just a proposal for an 
implementation that never happened.

Postgresql can detect conflicts on INSERT and perform an UPDATE instead 
(see https://www.postgresql.org/docs/current/sql-insert.html).  This is 
not exactly the same as Oracle's MERGE so you'll have to study it 
carefully to make you understand the nuances and be sure it works as 
intended in your application ... but it is the closest you can get using 
Postgresql.

George