Hi, In http://www.oracle.com/technology/oramag/oracle/05-nov/o65asktom.html, Tom Kyte described the differences between Oracle and non-oracle databases regarding the implementation of isolation levels. Not sure which non-oracle database he was referring to. but he made a point that other dbs use "shared read lock" for consistent answers which has a side effect: "Readers of data will block writers of data"
1) MySQL I donot know how isolation levels implemented in mysql .. I found this discussions - http://forums.mysql.com/read.php?97,75190,75584. Here the author gave an example of 2 concurrent transactions where one commits before the other. The results of the first are available in the second. I do not see anything wrong with that, may be I missed the point of the author. 2) PostGreSQL http://www.postgresql.org/docs/8.1/interactive/transaction-iso.html I read, reread, but could not completely grasp this. seems it's an esoteric topic for my level of expertise. My Question is, does ofbiz architecture ensure consistent isolation behavior across all/popular databses? Please advise if we need to think through this before choosing a database for our business needs regards Sastry
