× The internal search function is temporarily non-functional. The current search engine is no longer viable and we are researching alternatives.
As a stop gap measure, we are using Google's custom search engine service.
If you know of an easy to use, open source, search engine ... please contact support@midrange.com.


  1.  Home
  2. MIDRANGE-L
  3. April 2008

Classic trap : using SQL while not fully competent

I was going to cry for help :

I know I have a record on the left that ain't on the right so I did

SELECT * FROM prdcap exception join adhtst on ad1cad=tadhno
WHERE tcrtcd ='14'

Which returned no record.


But

SELECT * FROM prdcap WHERE P ad1cad not in
( select tadhno from adhtst where tcrtcd ='14')

Found the record.

After a while I thought, maybe its because tcrtcd is in the right hand table, so I tried
SELECT * FROM prdcap exception join adhtst on ad1cad=tadhno
and tcrtcd = '14'

Which worked.

Its the first time I put the where criteria in the JOIN. Can anyone give me the technical explication as to why the first example didn't work so I don't fall in again please ?

Thanks.


As an Amazon Associate we earn from qualifying purchases.

This thread ...
Follow-Ups:
Follow On AppleNews
Return to Archive home page | Return to MIDRANGE.COM home page

This mailing list archive is Copyright 1997-2024 by midrange.com and David Gibbs as a compilation work. Use of the archive is restricted to research of a business or technical nature. Any other uses are prohibited. Full details are available on our policy page. If you have questions about this, please contact [javascript protected email address].

Operating expenses for this site are earned using the Amazon Associate program and Google Adsense.