![]() You cannot use the ORDER BY clause in the CREATE VIEW statement however, the GROUP BY clause has the same effect as an ORDER BY clause when it’s used in the CREATE VIEW statement. If parent tables or views are dropped then child views are invalid. ![]() To create a view, a user must have the appropriate system privilege according to the specific implementation. You can create views from a single table, multiple tables, or another view. Views are created using the CREATE VIEW statement. Reduces writing complicated join queries. You can then give the temporary help access to the view to write the report without giving them access to the compensation columns in the table. To prevent that, you have created a view containing only the required information: employee name, address, and phone numbers. If you give access to EMPLOYEE_TBL to the temporary help, they can see how much each of your employees receives in compensation-you do not want this to happen. You have some temporary help come in to write a report of employees’ names, addresses, and phone numbers. EMPLOYEE_TBL includes employee names, addresses, phone numbers, emergency contacts, department, position, and salary or hourly pay. Let’s say you have a table called EMPLOYEE_TBL. Views can be utilized as a form of security in the database. it helps to hide columns having sensitive info in the underlying table. ![]() | testview | CREATE ALGORITHM=MERGE SQL SECURITY DEFINER VIEW `testview` AS select `dispatches_data`.`ProductName` AS `ProductName`,`dispatches_data`.`CustomerName` AS `CustomerName`,`dispatches_data`.`DispatchTimeStamp` AS `DispatchTimeStamp`,`dispatches_data`.`Price` AS `Price`,`dispatches_data`.It helps in providing security i.e. If you retrieve the definition of the above created view after altering the table you can observe the name of the algorithm − Mysql> ALTER ALGORITHM=MERGE VIEW testView AS SELECT * FROM dispatches_data | testview | CREATE ALGORITHM=UNDEFINED SQL SECURITY DEFINER VIEW `testview` AS select `dispatches_data`.`ProductName` AS `ProductName`,`dispatches_data`.`CustomerName` AS `CustomerName`,`dispatches_data`.`DispatchTimeStamp` AS `DispatchTimeStamp`,`dispatches_data`.`Price` AS `Price`,`dispatches_data`.`Location` AS `Location` from `dispatches_data` | cp850 | cp850_general_ci |įollowing query alters the ALGORITHM of the table − | View | Create View | character_set_client | collation_connection | You can retrieve the definition of the above created view using the SHOW CREATE VIEW statement as shown below − Mysql> CREATE VIEW testView AS SELECT * FROM dispatches_data Insert into dispatches_data values('Headset', 'Jalaja', TIMESTAMP('', '10:49:27'), 6000, 'Goa') Īssume we have created a view using the CREATE VIEW statement as shown below − Insert into dispatches_data values('Earphones', 'Roja', TIMESTAMP('', '14:13:12'), 2000, 'Vishakhapatnam') Suppose we have created a table named dispatches_data with 5 records in it using the following queries − Where, name is the name of the view for which you need the CREATE statement. Syntaxįollowing is the syntax of the ALTER VIEW Statement The MySQL SHOW CREATE VIEW Statement displays the CREATE VIEW statement used to create the specified view. It is stored in the database with an associated name. A MySQL view is a composition of a table in the form of a predefined SQL query.
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