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: From: "Bernhard Doebler" <programmer@b...>
: Subject: [sql_language] Basic knowledge
:
: can one of you please be so kind to explain the differences
: between clustered and unclustered indexes.
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Did you look in Books Online?
A clustered index means that the data is stored physically in that order on
the disk, making it easy to pull a number of sequential records. As well,
the index entries point to the physical location on the disk where the
record can be found.

A non-clustered index merely points to the location in the clustered index
where the record can be found. SQL Server then looks in the clustered index
for the physical location on the disk for the record

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: Can he also explain the difference between "simple" primary
: key and constraints?

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A primary key identifies a record uniquely. A constraint is something else -
look in Books Online.

Cheers
Ken