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can I do a join that shows what is 'not' in the other table?
mysql, query, join
sukebe




msg:4234627
 7:12 pm on Nov 24, 2010 (gmt 0)

I have two tables connected by 'pid'.
When setting a product up, there is an option to set a tax table. If none is set, the table 'tax' does not get an entry.

Can I use a join to show all pids in 'products' that are not in 'tax', or do I have to build a PHP routine to sift this out?

Thanks!

 

LifeinAsia




msg:4234636
 7:31 pm on Nov 24, 2010 (gmt 0)

Yup- LEFT OUTER JOIN is your friend!

Example:
SELECT Table1.pid
FROM Table1 LEFT OUTER JOIN Table2 ON Table1.pid=Table2.pid
WHERE Table2.tax IS NULL

sukebe




msg:4234736
 1:03 am on Nov 25, 2010 (gmt 0)

awesome! Thanks so much!

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