Thank you for true response will try out. Sajeev On 5/16/13 10:27 AM, "Steven Schlansker" <steven@xxxxxxxxxxxx> wrote: > >On May 15, 2013, at 11:52 PM, Thomas Kellerer <spam_eater@xxxxxxx> wrote: > >> Sajeev Mayandi, 16.05.2013 07:01: >>> Hi, >>> >>> Our company is planning to move to postreSQL. We were initially using >>> sybase where upsert functionality was available using "insert on >>> existing update" clause. I know there multiple ways to fix this >>> using RULE or separate function in postgresql. But I would like to >>> know which version of postgresql has support for upsert planned using >>> an official syntax. I have postgresql 9.2 which does not have this >>> feature, if its planned in near future, I would rather wait to >>> migrate to PostgreSQL. >>> >> >> You can use writeable CTEs for this purpose. >> >> There are several examples out there: >> >> http://www.xzilla.net/blog/2011/Mar/Upserting-via-Writeable-CTE.html >> http://www.depesz.com/2011/03/16/waiting-for-9-1-writable-cte/ >> http://www.depesz.com/2012/06/10/why-is-upsert-so-complicated/ >> >> http://stackoverflow.com/a/8702291/330315 > >One thing I didn't see mentioned in two of the links -- they mention race >conditions, where multiple writers can still cause the faked UPSERT to >fail. > >This can be avoided using SERIALIZABLE transactions, now that Postgres has >SSI. http://wiki.postgresql.org/wiki/SSI > >I can vouch that we use writable CTEs and SERIALIZABLE to implement UPSERT >in production with no issues thus far. > > > >-- >Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) >To make changes to your subscription: >http://www.postgresql.org/mailpref/pgsql-general -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general