Re: Constants in the foreighn key constraints

On 11/22/19 6:32 AM, aleksey ksenzov wrote:
> Hi team.
> Latest time we faced several issues which wouldn't arise provided we 
> have possibility to use constants in foreign key constraints.
> brief example where it would be helpful:
> 
> table_a
> ( id uuid,
> parent_id uuid,
> is_deleted boolean
> )
> having possibility of FK (parent_id, false) to (id, is_deleted)
> would disallow setting parent record deleted flag to true if they have 
> children, or insert record with is_deleted = true parent.

Postgres version?

Look at triggers, in particular CONSTRAINT triggers:

https://www.postgresql.org/docs/12/sql-createtrigger.html

> 
> Regards,
> Aliaksei.


-- 
Adrian Klaver
[email protected]