A SQL Server expert gives his take on the absolute, No. 1, very worst thing IT pros can do when it comes to indexing.

This article explores the internals of Oracle9i indexing; reviews the standard b-tree index, index-only tables, and how these indexes may increase the speed of Oracle SQL queries.

I need to delete a number of rows from a table. Should I have indexing on for the columns that I'm using to choose what to delete?

Read this SQL tutorial to learn when to use SELECT, JOIN, subselects and UNION to access multiple tables with a single statement.