What is the Use of using Where 1=1 in SQL Query

Hi Experts

What is the use of using where 1=1 in SQL Query Statement, This could be of great help to me

Regards

quote:Originally posted by vijai.krishnaraj

Hi Experts

What is the use of using where 1=1 in SQL Query Statement, This could be of great help to me

Regards

This means that the condition is always true.




SELECT * INTO Table1 FROM Table2 WHERE 1 = 1.




This will create table1 and populate data from table2.




SELECT * INTO Table1 FROM Table2 WHERE 1 = 0.

This will create table1 similar to Table2 but with No data.



Thanks,
DilliGrg

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Madhivanan</i><br /><br />It can be also used in While loop<br /><br />While 1=1<br />--some stuff<br /><br />Madhivanan<br /><br />Failing to plan is Planning to fail<br /><hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote"><br /><br />I guess that while loop would fall into the category of "long-running-queries"<br /><br />[<img src='/community/emoticons/emotion-5.gif' alt='' />] <br /><br /><br />"Follow the join tree" - Dan Tow

yes both scenarios are different

SURYA

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by eloop</i><br /><br /><blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Madhivanan</i><br /><br />It can be also used in While loop<br /><br />While 1=1<br />--some stuff<br /><br />Madhivanan<br /><br />Failing to plan is Planning to fail<br /><hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote"><br /><br />I guess that while loop would fall into the category of "long-running-queries"<br /><br />[<img src='/community/emoticons/emotion-5.gif' alt='' />] <br /><br /><br />"Follow the join tree" - Dan Tow<br /><hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">Correct, but you can always include the BREAK command to get out of the loop when a certain condition is met.<br /><br />The point is that you must build in a guaranteed break point, perhaps after the loop has continued for longer than a given amount of time.

quote:Originally posted by dineshasanka

SELECT * INTO Table1 FROM Table2 WHERE 1 = 0. Smart!!

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Thanks.
Don't know if the original poster got his concern addressed.

Thanks,
DilliGrg

quote:Originally posted by vsnreddi

yes both scenarios are different

SURYA

I absolutely agree.

Thanks,
DilliGrg

I use "SELECT * INTO Table1 FROM Table2 WHERE 1 = 0" to create table schema where I use WHILE 1=1 with BREAK to process records...

I also use WHILE 1 = 1 withour BREAK to run in an infinite loop.. ex:blocking script in a job...


Mohammed U.