May 2020
Beginner
564 pages
14h 9m
English
Content preview from Learn SQL Database Programming
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Understanding how to apply data types and data integrity to your table
Let's briefly review what we covered about data integrity in Chapter 1, Introduction to Relational Database Management Systems.
Database integrity refers to the consistency and accuracy of data. It is typically enforced by the procedures and guidelines in the database design phase. In RDMS, data integrity is enforced by using keys. A key forces values in a table to conform to a specified standard. There are many types of key to ensure data integrity and enforce table relationships:
| Entity integrity | Referential integrity | Domain integrity |
| Unique constraint | Foreign key | Check constraint |
| Not null constraint | Default constraint | |
| Primary key |
You need to remember ...
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