May 2020
Beginner
564 pages
14h 9m
English
Content preview from Learn SQL Database Programming
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Understanding data integrity
Data integrity refers to the consistency and accuracy of data. In RDMS, keys enforce data integrity. A key forces values in a table to conform to a standard that you specify in the key. It's essential to enforce data integrity in your database so that you have accurate and consistent data. You want to ensure that incorrect values don't wind up in the database. You also want to ensure that data isn't in the wrong format. You don't want users to be able to delete information from one table that another table relies on.
There are many types of keys to ensure data integrity and enforce table relationships or referential integrity, as shown in the following list. For more detail about this topic, go to Chapter 1
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