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From: Lennart Jonsson <erik.lennart.jonsson@gmail.com>
Newsgroups: comp.databases.ms-sqlserver
Subject: question on clustered indexes in sql-server
Date: Tue, 29 Nov 2011 16:39:57 +0100
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What is the purpose of a clustered index in sql-server (as you probably
have guessed I have zero to none experience with sql-server)?

The reason I ask is because I look at a databas where more or less all
tables are designed as:

create table T (
	x int IDENTITY(1,1) NOT NULL,
[...]
 CONSTRAINT ... PRIMARY KEY CLUSTERED ( x ) ...
	
In db2 I would look at range predicates and order by clauses on queries
to determine what index that should be clustered (inorder to avoid sorts).

What is the rationale to use a clustering index like the one above?

/Lennart