MySQL View or MySQL Virtual Table

View is a virtual table created by joining one or more tables.

MySQL Create VIEW

VIEW is created by SELECT statements. To make a VIEW, SELECT statements are used to take data from the source table.
Syntax:

    CREATE [OR REPLACE] VIEW view_name AS  
    SELECT columns  
    FROM tables  
    [WHERE conditions];

Here, OR REPLACE is optional which is used when a VIEW is already exist.
Example:

    CREATE VIEW trainer AS  
    SELECT course_name, course_trainer   
     FROM courses;

To see the created VIEW:

    SELECT * FROM view_name;

To modify or update the already created VIEW without dropping it, we have to use ALTER VIEW statement.
Syntax:

    ALTER VIEW view_name AS  
    SELECT columns  
    FROM table  
    WHERE conditions;

Example:

ALTER VIEW trainer AS  
SELECT course_name, course_trainer, course_id  
FROM courses;

We can drop VIEW using DROP VIEW statement.
Syntax:

    DROP VIEW [IF EXISTS] view_name;

Here, IF EXISTS is optional. If we do not specify this clause and the VIEW don’t exist, then the statement will return error.
Example:

    DROP VIEW trainer;