RE: EnterpriseDB

PostGreSql has probably the least problem with MVCC". I agree. autovaccum process exists since version 8.1, I believe. Thereis an backgroung jobs that analyzed automatically

the table. The aggressiveness of both autovacuum & analyze processed can be confugured (in the configuration file) A drawback of PG is that in case f UPDATE the whole row is coped (to represent the past version of the row), thus generating more REDO than necessary ;(  

-----Original Message-----
From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Richard J. Goulet Sent: Wednesday, February 21, 2007 9:45 PM To: Laimutis.Nedzinskas_at_landsbanki.is; oracle-l_at_freelists.org Subject: RE: EnterpriseDB

PostGreSql has probably the least problem with MVCC. In PostGreSql you don't delete or update a data record, but create a new one and stamp the old one with the current transaction ID. It works very well, but does require more maintenance from a process called Vacuum. But then the latest version of PostGresql runs that as an integral part of the database engine now. When a user starts a query they acquire the latest transaction ID and look at rows of that that were only in existence at that time. The Vacuum process prevents the transaction ID's from wrapping around which can cause all kinds of trouble.    

Dick Goulet, Senior Oracle DBA

45 Bartlett St Marlborough, Ma 01752, USA Tel.: 508.573.1978 |Fax: 508.229.2019 | Cell:508.742.5795

RGoulet_at_kanbay.com

: POWERING TRANSFORMATION  

From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Laimutis Nedzinskas Sent: Wednesday, February 21, 2007 1:19 PM To: oracle-l_at_freelists.org
Subject: RE: EnterpriseDB

As far as I understand the real issue about RDBMS performance is how(and if) they implement MVCC (multi version concurency control)  

From my understanding PostgreSQL as well as Firebird have some serious issues with that. Which is not the case with innoDB of MySQL, havenīt they ?    

From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Richard J. Goulet

Agree, I was asked to "pick my own poison" from the open source world a few years ago, before EnterpriseDB exited. If you are going to use an open source db I'd highly recommend PostGreSql over ALL of the other offerings out there, particularly MySql.    

Fyrirvari/Disclaimer
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