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From:sheeri kritzer Date:March 31 2006 3:16pm
Subject:Re: Table Type For PK/FK
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I didn't write the codebase for MySQL, so it's pointless to tell me
that "it's useless to be able to create a foreign key on a MyISAM
table".  I agree that it's useless, however, it's possible, which is
why I put it in there -- as a caveat.

The use is that apparently in future versions MyISAM will support
foreign key constraints.  It's a comment because it still shows up in
SHOW CREATE TABLE and such.

Like I said, I didn't design MySQL -- I just use it and was warning
that it's possible to create a table.  I've seen the dreaded Error
number 150 way too many times, and sometimes it's because I forgot the
"engine=innodb" part of the CREATE TABLE statement.

-Sheeri

On 3/31/06, Martijn Tonies <m.tonies@stripped> wrote:
> Hello Sheeri,
>
> > Indeed, only the BDB and InnoDB storage engines support referential
> > integrity.  If you accidentally create the table as MyISAM, there is
> > no error, though -- the constraints serve as a comment.
>
> No error? A comment? What use is that?
>
> If you want FKs, having the FKs as "a comment" is useless.
>
> Instead, re-create the table as of the InnoDB type.
>
> Martijn Tonies
> Database Workbench - development tool for MySQL, and more!
> Upscene Productions
> http://www.upscene.com
> My thoughts:
> http://blog.upscene.com/martijn/
> Database development questions? Check the forum!
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>
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Thread
Table Type For PK/FKScott Purcell31 Mar
  • Re: Table Type For PK/FKsheeri kritzer31 Mar
  • Re: Table Type For PK/FKMartijn Tonies31 Mar
  • Re: Table Type For PK/FKMartijn Tonies31 Mar
    • Re: Table Type For PK/FKsheeri kritzer31 Mar
      • Re: Table Type For PK/FKmysql31 Mar