What is index tuning

As all of us know it is very typical to choose column for non cluster index. We should consider creating non-cluster index on any column that are frequently referenced in the where clauses of Sql statements.we may wish to also consider creating non-clustered indexes that cover all of the columns used by certain frequently issued queries. These queries are referred to as covered queries and experience excellent performance gains. Index Tuning is the process of finding appropriate column for non-clustered indexes. SQL Server provides a wonderful facility known as the Index Tuning Wizard which greatly enhances the index selection process.

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