What are indexes? What is the difference between stered and nonclustered indexes

Q

What are indexes? What is the difference between clustered and nonclustered indexes?

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A

Indexes in SQL Server are similar to the indexes in books. They help SQL Server retrieve the data quickly.
There are clustered and nonclustered indexes. A clustered index is a special type of index that reorders the way in which records in the table are physically stored. Therefore table can have only one clustered index. The leaf nodes of a clustered index contain the data pages.
A nonclustered index is a special type of index in which the logical order of the index does not match the physical stored order of the rows on disk. The leaf node of a nonclustered index does not consist of the data pages. Instead, the leaf nodes contain index rows.

2007-10-25, 4417👍, 0💬