What must be followed for data and update operations in relational databases?

# Data and update operations in relational databases must follow integrity rules such as entity integrity, referential integrity, and user-defined integrity.

The relational model includes relational data structure, relational operation set and relational integrity. Relational integrity is data integrity, including entity integrity, referential integrity, and user-defined integrity.

Relational database is a database built on the relational database model. It uses concepts and methods such as set algebra to process data in the database. It is also a set of formally descriptive tables organized into a set. The essence of a formal table is to hold a special collection of data items. The data in these tables can be accessed or recalled in many different ways without the need to reorganize the database table.

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