SQLPlex | Database technology community - 5 Recently Added Articles http://www.sqlplex.com This RSS Feed contains 5 recently added articles to the knowledge base. You can click on the title to view its content. Knowledge Base (http://www.sqlplex.com) http://www.sqlplex.com/article-384.html Multiple column index vs multiple indexes http://www.sqlplex.com/article-384.html After my previous post there were questions raised about Index Merge on Multiple Inde]]> http://www.sqlplex.com/article-383.html 101 Reasons Why PostgreSQL is a better fit for Rails than MySQL http://www.sqlplex.com/article-383.html
MySQL cannot utilize more than one index per query. I believe this is worth repeating: MySQL CANNOT UTILIZE MORE THAN ONE INDEX PER QUERY. Wait till your tables get large enough and this will surely ]]> http://www.sqlplex.com/article-382.html New partitioning features http://www.sqlplex.com/article-382.html feature that partitioning makes possible. So I thought
it might be a good idea to mention a little bit what
we're doing in the area of partitioning. http://www.sqlplex.com/article-381.html Oracle Magazine - September/October http://www.sqlplex.com/article-381.html http://www.sqlplex.com/article-371.html Union vs Union All http://www.sqlplex.com/article-371.html In short, UNION does a sort-unique on both collections. UNION ALL just retrieves all rows, regardless of any double values.

I came across a (similar) piece of code during my work at BT: