What are the differences between database views and tables?

The differences between database views and tables are: 1. A table is a physical structure used to store data in a database, while a view is just a query result set based on a table or multiple tables; 2. A table is the physical storage of data. Units and views only provide rules for viewing and operating table data; 3. Views provide advanced security mechanisms for the database, and tables have no security mechanisms; 4. Views are abstractions of tables; 5. Views can combine multiple tables in queries. Only a single table can be queried; 6. Tables are permanent structures in the database, views are not; 7. Views can create views with the same name, but tables cannot create tables with the same name, etc.

# Operating system for this tutorial: Windows 10 system, Dell G3 computer.

Database views and tables are both important structures in the database, and they have significant differences in functions and characteristics. The following are the main differences between views and tables:

Physical existence:A table is a physical structure used to store data in a database, while a view is just a query result set based on a table or multiple tables, Does not have an independent physical existence. A view is actually a logical representation of one or more tables. It does not contain data, but only references and operation rules to the data in the tables.

Data operation: Table is the physical storage unit of data, which can perform operations such as adding, deleting, modifying, and querying data. The view only provides a specific perspective and rules for viewing and operating table data. Therefore, the operation on the view is actually an indirect operation on the table.

Security: Views provide a more advanced security mechanism for the database. Through views, users can only access part of the data in the tables they are authorized to access, which greatly improves data security. The table does not have such a security mechanism. It exposes all data and has no restrictions on user access.

Level of abstraction: The view is an abstraction of the table. It hides the details in the table and only displays the information that the user cares about. This allows users to manipulate data without knowing the specific structure of the table. Tables provide lower-level, more direct data access.

Complex queries: Views can combine multiple tables in one query, even using complex SQL statements. Tables can only perform simple queries on a single table.

Temporary and permanent: Tables are permanent structures in the database, while views can be created or deleted at any time and have no permanence.

Naming conflict: Since views are logical structures, it is possible to create views with the same name but based on different tables. In the database, tables and views with the same name will not have naming conflicts.

In short, views and tables each play an important role in the database. The table is the physical storage unit of data, providing the most basic data operations; while the view is the logical representation of the table, providing more advanced data operation methods, security, and abstraction layers. Based on actual needs, you can choose to use views or tables to meet specific data manipulation and analysis needs.

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