Can a foreign key be linked to a non-primary key?

Can a foreign key be linked to a non-primary key?

A foreign key can refer to either a unique or a primary key of the parent table. If the foreign key refers to a non-primary unique key, you must specify the column names of the key explicitly.

How do you create a foreign key relationship in SQL?

Using SQL Server Management Studio

1. In Object Explorer, right-click the table that will be on the foreign-key side of the relationship and click Design.
2. From the Table Designer menu, click Relationships.
3. In the Foreign-key Relationships dialog box, click Add.
4. Click the relationship in the Selected Relationship list.

Does a primary key have to have a foreign key?

Primary keys always need to be unique, foreign keys need to allow non-unique values if the table is a one-to-many relationship. Yes, it is legal to have a primary key being a foreign key.

How do you create a relationship to a non primary key in?

Is there any way I can get the cascade update/delete feature without changing the users table so that UserName is the primary key and not UserID? Create a unique index or unique constraint on UserName then you can reference it in a FK constraint fine. is incorrect.

How to create a foreign key relationship in SQL Server?

Create a foreign key relationship in Table Designer Using SQL Server Management Studio In Object Explorer, right-click the table that will be on the foreign-key side of the relationship and click Design .

How do I create a primary key in a table?

Creating a primary key in an existing table requires ALTER permission on the table. In Object Explorer, right-click the table to which you want to add a unique constraint, and click Design. In Table Designer, click the row selector for the database column you want to define as the primary key.

How to create a relationship in SQL Server?

They are both unique but I decided for reasons to use the UserName as a reference in other tables. So the order table for example has a reference to user by UserName not userid. I want to create a relationship between all tables that reference the UserName and the Users table so that I get the cascade update/delete feature of SQL Server.