NYCPHP Meetup

[cesar]

yeap, thats the charm.

thank you.

On Tue, 6 Aug 2002, Carlos A Hoyos wrote:

>
> Nice try, but mysql doesn't support subselects... :(
>
> You can use left joins:
>
> SELECT aaa.a from aaa LEFT JOIN bbb on bbb.b = aaa.a where bbb.b IS NULL ;
>
> this query will return all values in a that are not in b.
>
> enjoy!
>
>
>
>
>                       "Jim Hendricks"
>                       <jim at bizcomputing        To:       NYPHP Talk <talk at nyphp.org>
>                       inc.com>                 cc:
>                                                Subject:  Re: [nycphp-talk] simple mysql query help
>                       08/06/2002 11:24
>                       AM
>                       Please respond to
>                       talk
>
>
>
>
>
> SELECT * FROM aaa WHERE aaa.ID NOT IN( SELECT ID FROM bbb )
>
> DELETE FROM aaa WHERE aaa.ID NOT IT( SELECT ID FROM bbb )
>
> aaa.ID and ID are the key fields which link aaa to bbb.
>
> HTH,
> Jim
>
> ----- Original Message -----
> From: "cesar" <can at andrew.cmu.edu>
> To: "NYPHP Talk" <talk at nyphp.org>
> Sent: Tuesday, August 06, 2002 11:16 AM
> Subject: [nycphp-talk] simple mysql query help
>
>
> >
> > i have two tables aaa and bbb
> > aaa has {1 , 2}
> > bbb has {1 , 3 }
> >
> > i want select those values in aaa that don't appear in bbb, and also
> > another query that will delete those values in aaa which don't appear in
> > bbb. if someone can please help me, i'm just a little stuck. i know i
> > figured it out before, but right now i have no clue.
> >
> >  A)
> > mysql> select * from aaa;
> > +------+
> > | a    |
> > +------+
> > |    1 |
> > |    2 |
> > +------+
> >
> > mysql> select * from bbb;
> > +------+
> > | a    |
> > +------+
> > |    1 |
> > |    3 |
> > +------+
> >
> > B)i understand why this does what it does, but how do i correct it?
> > mysql> select aaa.*, bbb.* from aaa, bbb where aaa.a != bbb.a;
> > +------+------+
> > | a    | a    |
> > +------+------+
> > |    2 |    1 |
> > |    1 |    3 |
> > |    2 |    3 |
> > +------+------+
> >
> > thnka you in advance.
> >
> >
> >
> >
> >
>
>
>
>
>
>
>
>
>
>
>