How to eliminate duplicate rows from two tables?

Wilfred · New User Joined: 06 Feb 2007 Posts: 5 Location: bangalore

Hi All

Can any one tell me how to eliminate duplicate rows from two tables? please! i know to eliminate duplicate rows from a table we can use DISTINCT. but for from two tables?

Thank you
Regards
Wilfred

William Thompson · Posted: Wed Feb 07, 2007 1:14 am

I obviously do not understand because my first suggestion would be to use two DISTINCTs.....But I don't expect that is what you want....
Could you expand on the problem a little?

Wilfred · New User Joined: 06 Feb 2007 Posts: 5 Location: bangalore

Hi

i mean to say, i have tableA and tableB, and i want to eliminate duplicate rows from these two tables.

I think we can use logic UNION and UNION ALL

UNION IS FOR TO ELIMINATE DUPLICATE ROWS AND
UNION ALL IS GET THE DUPLICATE ROWS.

CORRECT ME IF AM WRONG!
THANKS
WILFRED!

rajeshps19 · New User Joined: 14 Feb 2007 Posts: 4 Location: Noida

Hi Wilfred,

Yes, that's right.

UNION will eliminate all duplicate rows whereas UNION ALL will retain them.

Rajesh.