The command to create a view in sql is

Command to create a view in SQL: CREATE VIEW [schema name.] view name AS SELECT, used to derive virtual data from tables, providing data abstraction, security, performance optimization and reuse.

The command to create a view in SQL

The command to create a view is:

<code class="sql">CREATE VIEW [模式名称.]视图名称 AS SELECT 列名 [, 列名 ...] FROM 表名 [WHERE ...]</code>

Command structure

• #Mode name (optional): Specify the mode to which the view belongs. If not specified, the view will be created in the default mode.
• View name: The name of the view to be created.
• Column name: The name of the column selected from the table.
• Table Name: The name of the table from which data is retrieved.
• WHERE clause (optional): Used to filter table rows based on specific conditions.

Command Example

To create a view named Customer View, which is derived from the Customer table To select the CustomerID, CustomerName, and Email columns, you can use the following command:

<code class="sql">CREATE VIEW 客户视图 AS 
SELECT 
    客户 ID, 
    客户姓名, 
    电子邮件 
FROM 
    客户表</code>

Purpose of the View

Views provide the following benefits:

• Virtual tables: Views are not actual tables, but virtual tables derived from underlying tables.
• Data abstraction: Views allow you to extract data from multiple tables or complex queries, hiding the underlying table structure and query logic.
• Data security: Views can restrict users who access sensitive data in the underlying tables.
• Performance optimization: Views can store pre-calculated results, thereby improving the performance of complex queries.
• Data reuse: Views can be created so that data can be reused across multiple queries or applications.

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