Access foreign key not updating
This topic describes how to create foreign key relationships in SQL Server 2017 by using SQL Server Management Studio or Transact-SQL.
You create a relationship between two tables when you want to associate rows of one table with rows of another.
The primary key for each table is stored in an index.
The index is used to enforce the uniqueness requirement.
It also makes it easy for foreign key values to refer back to corresponding primary key values, as we will learn about in the following section. Business Entity ID is not only a foreign key, but is also part of Person Phone’s primary key.
In this article we learn the difference between a primary key and a foreign key, and why both are important to maintaining a relational database structure.In order to be a primary key, several conditions must hold true.First, as we mentioned, the columns must be unique.All the examples for this lesson are based on Microsoft SQL Server Management Studio and the Adventure Works2012 database.You can get started using these free tools using my In order for a table to qualify as a relational table it must have a primary key.