What would be the primary key in the customers and orders table?

Question

Notice that the customer number column is the primary key of the customers table and that the same column is a foreign key in the orders table. The customer number column in orders therefore serves to relate orders to the customers to which they belong.

What is the primary key of the customer table?

Often, a unique identification number, such as an ID number or a serial number or code, serves as a primary key in a table. For example, you might have a Customers table where each customer has a unique customer ID number. The customer ID field is the primary key.

How do you find primary keys in a table?

Primary Keys. The primary key of a table is the column whose values are different in every row. Because they are different, they make each row unique. If no one such column exists, the primary key is a composite of two or more columns whose values, taken together, are different in every row.

Which field is designated as the primary key in the Orders table?

Each database table must have a field or a combination of fields that holds a value that uniquely identifies each record. For example, a customer number would uniquely identify each customer. This field or fields are called the primary key of the table.

What is a primary key with example?

A primary key is a column -- or a group of columns -- in a table that uniquely identifies the rows of data in that table. For example, in the table below, CustomerNo, which displays the ID number assigned to different customers, is the primary key.

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