• Clustered Index
  1. A clustered index is a special type of index that reorders the way records in the table are physically stored.
  2. Therefore table can have only one clustered index. The leaf nodes of a clustered index contain the data pages.
• Non-Clustered Index
  1. 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.
  2. The leaf node of a nonclustered index does not consist of the data pages. Instead, the leaf nodes contain index rows.

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