Re: Constraint + where

[Melvin Davidson <melvin6925@xxxxxxxxx>]

On Sun, Mar 19, 2017 at 8:27 PM, Melvin Davidson <melvin6925@xxxxxxxxx> wrote:

On Sun, Mar 19, 2017 at 8:16 PM, Patrick B <patrickbakerbr@xxxxxxxxx> wrote:

Hi guys,

I've got a column 'type_note' on a new table that it's being designed:

type_note varchar(32) NOT NULL;

On that column, there will be three different data:

1. yes

2. no

3. maybe

I wanna create a FK but just when the data on that column is = maybe.

How can I do that? Thanks!

Why just "maybe"? Since there can only be three valid answers, why not FK for all three?

--

Melvin Davidson
I reserve the right to fantasize.  Whether or not you
wish to share my fantasy is entirely up to you.

Also "type_note varchar(32) NOT NULL;" is pointless.

You should make it either type_note(1)  with values of Y,N or M.

--

Melvin Davidson
I reserve the right to fantasize.  Whether or not you
wish to share my fantasy is entirely up to you.