[Database series]-differences between views and basic tables

View definition: (User) view views View data in the database from a specific perspective, just like a table. The (inside the database system) view is a virtual table defined by a query composed of SELECT statements. Advantages of a view: the view is connected to a basic table. A view is a table created on top of a basic table. Its structure (that is, the defined column) and content

View definition: (user perspective) views View data in the database from a specific perspective, just like a table. The (inside the database system) view is a virtual table defined by a query composed of SELECT statements. Advantages of a view: the view is connected to a basic table. A view is a table created on top of a basic table. Its structure (that is, the defined column) and content

View definition:

(User perspective) The view is fromSpecific AngleTo view the data in the database, the view is like a table.

The (inside the database system) view is a virtual table defined by a query composed of SELECT statements.

Advantages of a view:

View and basic table contact:

A view is a table created on top of a basic table. Its structure (that is, the defined column) and content (that is, all data rows) come from the basic table, it exists based on the basic table. A view corresponds to one or more basic tables. A view is the abstraction of a basic table and the new relationship established in a logical sense.

Differences between a view and a basic table:

Operation: views are suitable for multi-table join browsing and are not suitable for addition, deletion, and modification.

Space: Table-physical space; view-logical existence; virtual table

Modify: The table can be modified in time; the view can only be modified by the creation statement.

Nature: view is a way to view Data Tables (a set of SQL statements)

View considerations:

A view cannot reference any other view. It can only reference a base table.

All base tables referenced by a view must be in the same database as the view, and the owner must be the same as the view.

Large data volume and multi-Table Association are required. Do not use view indexes whenever possible.