Basic MySQL. XOR?

ps fred at planetaryserver.com
Mon Oct 30 10:17:54 EST 2006


This is sorta tangential to your question.

I question are you using MySQL 4.x or 5.x?

This is important, because the SQL semantics have changed a bit to make it 
compliant with the standard.

As such, there are a number of subtle differences which may bite and be hard 
to trace down unless you are aware of them.

One of those subtleties is the meaning of "," vs. "JOIN" in doing joins. In 
4.x, there was no difference. In 5.x there is a subtle difference. The 
difference is annoying enough that I have stopped using the "," altogether 
and simply use "JOIN". 

May not apply in your case at all, nonetheless, it is something to be aware 
of for those using 5.x or are contemplating migrating to it. I would 
strongly recommend reading the migration notes on the MySQL site for those 
concerned.

On Monday 30 October 2006 09:53, Dwight E Chadbourne uttered thusly:
> I was at work stuck using Access and it's GUI and just couldn't my query
> to work right.  There's an automatic join when you add tables and I didn't
> feel like using that app anyway.  I'm on a box with lots of software I
> don't like and I'm not root.  So I thought I'd ask the BLU list prior to
> running to my house and doing this on my home computer.  I kind of did
> what Seth said with success.
>
> SELECT csv1.*, csv2.varA FROM csv1, csv2
> WHERE csv1.varA = csv2.varA
> AND csv1.varB = csv2.varB
> AND csv1.varC = csv2.varC
> INTO blah blah blah
...

--Fred
--Planetary Server
  Global Technology for a Global Reach

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