In this post, I wanted to write about the covering index and key lookup and how adding covering indexes can help increase performance by reducing lookups to the table data. It's helpful to know what each of these terms mean and then we will look at an example scenario further down the post. What is a covering index? A covering index is a non-clustered index which includes … [Read more...] about SQL Server covering index and key lookup performance
SQL Server Performance
Solid state hard drives or SSD's as they are also known are the latest generation of hard disk storage. They are far superior to traditional hard disk drives because of the absence of moving parts and so are blisteringly faster in comparison. Due to the architecture of the platter based hard disk, it is much slower than other parts of the server and can typically be the … [Read more...] about Will solid state hard drives negate the need to performance tune your database server?
The following tips do not promise that your database server will magically become blisteringly fast and go like a Ferrari but they are important things to bear in mind and relatively simple to implement either when building your database or if you have an existing performance problem and are looking for ways in which to make your database run faster. 1/ SELECT * FROM The rest … [Read more...] about 10 simple tips on improving query and server performance
GROUPING SETS is a way of aggregating data to produce a result set containing different sets of columns. For the SQL Server platform, it was first introduced in SQL 2008. Prior to SQL Server 2008, achieving this type of result set was possible using UNION, WITH CUBE, WITH ROLLUP and a helper function called GROUPING to achieve similar results. The issues with WITH CUBE … [Read more...] about GROUPING SETS performance versus UNION performance