Re: constrain with MATCH full and NULL values in referenced table - Mailing list pgsql-general

From Adrian Klaver
Subject Re: constrain with MATCH full and NULL values in referenced table
Date
Msg-id 71e23df2-57ea-9d53-da33-5a5a0d4d695d@aklaver.com
Whole thread Raw
In response to constrain with MATCH full and NULL values in referenced table  (stan <stanb@panix.com>)
List pgsql-general
On 8/12/19 8:11 AM, stan wrote:
> I am creating a table that has 2 values in it which are keys pointing to 2
> other tables. I need for the UNIQUE combination of these 2 keys to exist in
> a fourth table. It has been recommended to use a foreign key constraint with
> the MATCH FULL parameter.

Without the table schema it difficult for me to figure out what it is 
you are attempting.

See below for how MATCH FULL works:

https://www.postgresql.org/docs/11/sql-createtable.html

> 
> Here is my question, does this deal with NULLS in the 4th table? I am
> concerned that this constraint might fail to reject an entry if one, or both
> of the 2 key values being inserted in the table are NULLS,.
> 
> 
> 


-- 
Adrian Klaver
adrian.klaver@aklaver.com



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