Tag: unique-constraint

Nasty sql error(POSTGRES) “There is no unique constraint matching given keys for referenced table…”

ddl foreign-keys postgresql sql unique-constraint

EDIT: tables have been translated from my language to english i’ve changed te reference of foreign key in table Comment to “Utente” -> “User” Hi everyone i’m trying to build a small review system in sql as follows. Every user can comment on some item(could be anything) and any other user can answer any comment. The Admin of the website

Set some default guid value in uniqueidentifier in sql

default default-value sql unique-constraint

I need to set default guid value, not NEWID() in uniqueidentifier column in SQL. For example: Have a column TestID in TestTable, need to set default TestID to “DA74F684-B228-48D5-9692-69465BE6D720”. Thank you in advance. Answer Here’s your script. then, update exsting records

How to create a constraint for conditional unique values?

check-constraints constraints sql sql-server unique-constraint

I am using SQL Server. I have this table: CREATE TABLE Student ( ID int PRIMARY KEY, FirstName varchar(100), LastName varchar(100), Active bit; ) I want to have unique(FirstName, …

Can I add a UNIQUE constraint to a PostgreSQL table, after it’s already created?

database indexing postgresql sql unique-constraint