A primary key is combined with a foreign key creates

A relationship between two tables in a database.

Here are the steps:

1. A primary key is a unique identifier for a record in a database table. It is a column (or set of columns) whose values uniquely identify every row in the table.

2. A foreign key is a field (or collection of fields) in one table, that is used to "refer" to the primary key in another table. The table with the foreign key is called the child table, and the table with the primary key is called the referenced or parent table.

3. When a primary key is combined with a foreign key, a relationship is created between the two tables. This relationship allows the database to match records in the child table with corresponding records in the parent table.

4. This relationship can be one-to-one, one-to-many, or many-to-many, depending on the number of records in each table that can be linked to records in the other table.

5. The use of primary and foreign keys to create relationships between tables is a fundamental aspect of relational database design. It allows for efficient data retrieval and ensures data integrity by preventing inconsistencies and duplication.