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@xxxxxxxxxxx