How to use a cross column exclude constraint - Mailing list pgsql-novice

From awolchute@tutanota.com
Subject How to use a cross column exclude constraint
Date
Msg-id NA0w1JZ--J-2@tutanota.com
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Responses Re: How to use a cross column exclude constraint
List pgsql-novice

Hi All,

Schema:
CREATE TABLE record (        id uuid primary key default ...,    ...
);

CREATE TABLE record_pointer (    id uuid primary key default ...,    record_a_id uuid not null references record (id),    record_b_id uuid not null references record (id),    ...
);

I am trying to create an exclude constraint to make both record_a_id and record_b_id unique table wide, so that each row from "record" can ever be referenced once in "record_pointers". 

Eg. if I add a record_pointer row that has "this-is-random-uuid" as record_a_id, the value "this-is-random-uuid" can never be in record_a_id or record_b_id in any other row.


Thank you in advance!


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