how does sql count work?

Posted by ria on Stack Overflow See other posts from Stack Overflow or by ria
Published on 2010-06-15T12:01:21Z Indexed on 2010/06/15 12:12 UTC
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I would like to understand how exactly does sql count work. Is it a whole table scan that happens or is it some property of the table that is read. However I feel a table scan would be an overhead in case of huge tables with lots of records.

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how does sql count work? - Developer IT

how does sql count work?

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Related posts about sql

SQL SERVER – Concat Strings in SQL Server using T-SQL – SQL in Sixty Seconds #035 – Video

SQL SERVER – Concat Function in SQL Server – SQL Concatenation

Error with SQL Server Setup 2012 on Windows 2012

How can I detect which version of SQL (eg SQL 2008 or SQL Azure)

Nested SQL Select statement fails on SQL Server 2000, ok on SQL Server 2005

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