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Database Optimization Techniques to Increase SQL SERVER Performance – Part III – Index on multiple columns
May 23rd, 2009
Macronimous Posted in Databases, web programming | 1 Comment »
Index on multiple columns for SQL performance
Since clustered index reorders the table and arranges the data according to the index key, SQL Server allows only one clustered index per table. This results in amazing performance, when you only have to worry about one particular column. If you are in need to order the data by more than one column. Since we can’t use clustered index for multiple columns, unclustered index are used to gain a performance increase. We can specify a key value for every unclusterd index, plus the value obtained from cluster index; which acts as a pointer to the actual values when we need their data. If unclustered index is keyed on the values needed for a given task then query engine will never be in need of visiting the actual rows. After learning everything it needs from the index and scope then it will visit the qualifying rows.
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June 2nd, 2009 at 4:58 am
Don’t think that performance tuning your SQL Server applications is regulated to the end of the development process. If you want your SQL Server-based applications to scale and run at their full potential, you must begin considering scalability and performance issues during the early stages of your application’s development.