May 2020
Beginner
564 pages
14h 9m
English
Content preview from Learn SQL Database Programming
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Understanding one-to-one table relationships
In a one-to-one relationship, one table has just one corresponding row in another table. An example of this could be two tables, one with employees and one with computers. Each employee has one computer. A one-to-one relationship is not a common table relationship. You might separate a table's data into multiple tables for security purposes—for example, you could have a table of employees, but want the pay in a separate table so that only certain people can access the employee pay information.
The following screenshot shows an example of a one-to-one relationship:
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