Re: How to insert record only if primary key does not exist

Craig Ringer <ringerc@xxxxxxxxxxxxx> · Sun, 01 Jul 2012 22:19:08 +0800



    On 06/30/2012 09:02 PM, Andrus wrote:

    
                Table is defined as
                 
                CREATE TABLE firma1.klient (
                  kood character(12) NOT NULL DEFAULT
                  nextval('firma1.klient_kood_seq'::regclass),
                ....
                );
                 
                How to insert record to this table only if primary
                  key does not exist ?

                
    You want an operation that's called an UPSERT or MERGE operation.
    PostgreSQL doesn't have any native support to do this for you. Doing
    it right is surprisingly tricky. This is the best article I've seen
    on the topic:

    
    http://www.depesz.com/2012/06/10/why-is-upsert-so-complicated/

    
    --

    Craig Ringer