Thread: foreign key is from different tables - what to do?

foreign key is from different tables - what to do?

From
"Cyril Samovskiy"
Date:
hi. i'm rookie in postgres, so here is my question:
i have foreign key consisting of 2 fields (a and b). a is foreign key from
table aaa, b is FK from table bbb. how to create table is that complex
foreign key consisiting of fields from different tables?
thank you

-------------------
Best regards,
Cyril Samovskiy
cyril_s31@yahoo.com
cyril@somiconline.org





Re: foreign key is from different tables - what to do?

From
Oliver Elphick
Date:
On Wed, 2002-02-20 at 18:23, Cyril Samovskiy wrote:
> hi. i'm rookie in postgres, so here is my question:

Therefore your question should have gone to pgsql-novice.  (Reply-To set
there.)

> i have foreign key consisting of 2 fields (a and b). a is foreign key from
> table aaa, b is FK from table bbb. how to create table is that complex
> foreign key consisiting of fields from different tables?
> thank you

You seem to have two foreign keys, not one.  I'm guessing that you
actually have a multi-field primary key, each field of which is a
foreign key to another table:

CREATE TABLE aaa (id INTEGER PRIMARY KEY, ...)
CREATE TABLE bbb (id INTEGER PRIMARY KEY, ...)
CREATE TABLE ccc (a INTEGER REFERENCES aaa(id),                 b INTEGER REFERENCES bbb(id),                 ...,
          PRIMARY KEY (a, b))
 

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