Can Anyone explain why NULL is used in this query?

Posted by Rishabh Ohri on Stack Overflow See other posts from Stack Overflow or by Rishabh Ohri
Published on 2010-03-24T10:54:37Z Indexed on 2010/03/24 11:03 UTC
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Also what will be the scenarios where this query is used

select * from TableA where exists  
    (select null from TableB where TableB.Col1=TableA.Col1)

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Developer IT

Can Anyone explain why NULL is used in this query? - Developer IT

Can Anyone explain why NULL is used in this query?

sql

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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