Can I have 2 foreign keys reference the same primary key?

Can I have 2 foreign keys reference the same primary key?

A Foreign Key is a database key that is used to link two tables together. The FOREIGN KEY constraint differs from the PRIMARY KEY constraint in that, you can create only one PRIMARY KEY per each table, with the ability to create multiple FOREIGN KEY constraints in each table by referencing multiple parent table.

Can there be multiple foreign keys in a relation?

A table may have multiple foreign keys, and each foreign key can have a different parent table. Each foreign key is enforced independently by the database system. Therefore, cascading relationships between tables can be established using foreign keys.

Can you have multiple of the same primary key?

No. You cannot use more than 1 primary key in the table. for that you have composite key which is combination of multiple fields. It needs to be a composite key.

Can multiple foreign keys reference the same table?

You can add more than one foreign key constraint to a single column. For example, if you create the following tables: CREATE TABLE customers ( id INT PRIMARY KEY, name STRING, email STRING );

Can a primary key be used as a foreign key twice?

yes, there is no problem with that…you can use a primary key of one table in other table as foreign key two times.

Is it possible to reference fields other than the primary key?

In fact, you could reference fields other than the primary key, if all you need is to use the value for joins. However, a foreign key constraint tells the database to enforce the rule that for every foreign key value in a table, the referenced table has a record with that as it’s primary key.

Is there a limit to the number of foreign key references?

Greater than 253 foreign key references are not currently available for columnstore indexes, memory-optimized tables, Stretch Database, or partitioned foreign key tables. Unlike primary key constraints, creating a foreign key constraint does not automatically create a corresponding index.

Is it OK to have two foreign key columns?

It is perfectly fine to have two foreign key columns referencing the same primary key column in a different table since each foreign key value will reference a different record in the related table.