OraFAQ Forum: SQL & PL/SQL » Multiple Column Sub Query

Home » SQL & PL/SQL » SQL & PL/SQL » Multiple Column Sub Query (Oracle 9i)

Show: Today's Messages :: Polls :: Message Navigator
E-mail to friend

Multiple Column Sub Query [message #394587]

Sat, 28 March 2009 00:14

ygsunilkumar
Messages: 100
Registered: August 2008

Senior Member

Please any one tell me What is the purpose of using Multiple Column Sub Query and When and why it is used? It is an Interview Question.

Report message to a moderator

Re: Multiple Column Sub Query [message #394605 is a reply to message #394587]

Sat, 28 March 2009 07:04

ehegagoka
Messages: 493
Registered: July 2005

Senior Member

do you mean an inline view?

Report message to a moderator

Re: Multiple Column Sub Query [message #394623 is a reply to message #394587]

Sat, 28 March 2009 12:58

cookiemonster
Messages: 13967
Registered: September 2008
Location: Rainy Manchester

Senior Member

I would assume it means what it says, i.e

SELECT *
FROM table1
WHERE (col1, col2) NOT IN (SELECT col3, col4 FROM table2);

It's purpose is exactly the same as a normal sub-query in a where clause except for the number of columns checked.

So that query returns rows where the combo of col1 and col2 don't match any of the combos of col3 and col4 in table2.

I leave it to you to think of a real world example where it'd be useful.

Report message to a moderator

Previous Topic:	Send Message From Oracle To Mobile Device
Next Topic:	Oracle 9i- Installation

Goto Forum:

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

]

Current Time: Sun Jul 13 00:16:15 CDT 2025