… chose if there is one – it is often a lot faster to retrieve rows in order checking WHERE clause for them… and checking if it matches our original WHERE clause with subselects. It looks scary if we look at EXPLAIN but in… not the most optimal. We do not really need separate subselect to make MySQL check WHERE clause while scanning table in…
Post: Derived Tables and Views Performance
August 31, 2006 By 14 Comments
… for what is called derived tables, inline views or basically subselects in the from clause. In MySQL 5.0 support for… query it will be faster in most cases. In many cases even separate temporary table will be faster as you can add… instead of derived tables If you really need to use subselect in from clause consider creating view using it in the…
Post: MySQL and PostgreSQL SpecJAppServer benchmark results
July 25, 2007 By 13 Comments
… a properly tuned PostgreSQL is not only as fast or faster than MySQL, but almost as fast as Oracle (since the… 12 cores. This seems to show PostgreSQL is some 10% faster, from the glance view. If you take a closer look… are faster others are slower in MySQL. For example PostgreSQL is slower at connection creation and MySQL is very fast, while SubSelect…
Comment: Derived Tables and Views Performance
August 31, 2006 By 14 Comments
… explain the speed difference). Probably the execution of the subselect is faster/less of a memory hog than creating the view, so…
Post: Database problems in MySQL/PHP Applications
August 11, 2006 By 12 Comments
…_increment is used so using values generated elseware might be faster. 3. Using multiple databases Honestly I do not see application… queries in this case. This most applies to subqueries Where Subselects with IN() become corellated even if they are not, and…
Comment: Database problems in MySQL/PHP Applications
August 11, 2006 By 12 Comments
…_increment is used so using values generated elseware > might be faster. I disagree with you on this completely because InnoDB uses… queries in this case. > This most applies to subqueries Where Subselects with IN() become > corellated even if they are not, and…
Post: MySQL Query Cache
July 27, 2006 By 69 Comments
…. Caching full queries only – Meaning it does not work for subselects, inline views, parts of the UNION. This is also common… caching but you can enable query cache so it works faster. Low load applications – If you’re building application which is…
