Re: sql Vs RLA to test existance

David,

IIRC, EXISTS stops as soon as it finds the first record. The syntax is:

SELECT * FROM TABLE1 WHERE EXISTS(SELECT 1 FROM TABLE2 WHERE TABLE1.FIELD
= TABLE2.FIELD) ;

Regards,
Luis Rodriguez
IBM Certified Systems Expert — eServer i5 iSeries
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On Tue, Feb 15, 2011 at 10:14 AM, David FOXWELL <David.FOXWELL@xxxxxxxxx>wrote:

Hi,

I need to find if a transaction of a particular type and amount exists for
a client.

I cannot remember how to apply the SQL Exists( ) to look for the
transaction.

Select '1' from ???? where exists ( select * from mytable where myfield =
'myfield')


Then again, I seem to remember that EXists will scan all the rows and not
just stop at the first one that satisfies the search criteria as I could do
with RLA.

Can someone put me straight please?

Thanks.

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