Re: SQL in constraints

mgumbs_at_hotmail.com wrote:

> Is it possible to use SQL in constraints?
>
> e.g Create table football.....
> ...
> ...
> Constraint rs_football_name
> check name in (select name from register where....)

No, you cannot use check on queries that retrieves data, or on another table such as register.

>
> If not, are there any alternatives? I have thoought of a pre-insert trigger
> but is there anything else?

You could write out all the values such as:

    check name in ('name1', 'name2', 'name3'...)

Or, try to create a foreign key on rs_football_name that refers back to register.name.

Feng

>
> Replies by e-mail if poss.
>
> Mark
>
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Received on Mon Mar 01 1999 - 12:59:42 CST