What is a MySQL view?

What is the use of MySQL view?

VIEWS are virtual tables that do not store any data of their own but display data stored in other tables. In other words, VIEWS are nothing but SQL Queries. A view can contain all or a few rows from a table. A MySQL view can show data from one table or many tables.

What are the advantages of views in MySQL?

What are the benefits of using MySQL views as compared to selecting data directly from MySQL base tables?

  • Simplify data access. …
  • Improves data security. …
  • Reduce data distraction. …
  • Preserves the appearance of original table structure. …
  • Implements all queries.

How do I create a view in MySQL?

By default, a new view is created in the default database. To create the view explicitly in a given database, use db_name. view_name syntax to qualify the view name with the database name: CREATE VIEW test.

What is an SQL view and why is it useful?

Views are virtual tables that can be a great way to optimize your database experience. Not only are views… Views are virtual tables that can be a great way to optimize your database experience.

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What triggers MySQL?

A trigger in MySQL is a set of SQL statements that reside in a system catalog. It is a special type of stored procedure that is invoked automatically in response to an event. Each trigger is associated with a table, which is activated on any DML statement such as INSERT, UPDATE, or DELETE.

Are MySQL views faster than queries?

No, a view is simply a stored text query. You can apply WHERE and ORDER against it, the execution plan will be calculated with those clauses taken into consideration.

What is the benefit of view?

Views can provide advantages over tables: Views can represent a subset of the data contained in a table. Consequently, a view can limit the degree of exposure of the underlying tables to the outer world: a given user may have permission to query the view, while denied access to the rest of the base table.

What is a view what are the advantages and disadvantages of using a view?

Views are used for security purpose in databases,views restricts the user from viewing certain column and rows means by using view we can apply the restriction on accessing the particular rows and columns for specific user.

Which types of views Cannot be updated?

What types of database views cannot be updated? You cannot update views that involve statistics and views with joins of nonprimary key columns. Updates for these types of views must be made in the base table. Use the DROP VIEW command to delete a view.

Is updatable MySQL view?

Introduction to MySQL updatable views

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In MySQL, views are not only query-able but also updatable. It means that you can use the INSERT or UPDATE statement to insert or update rows of the base table through the updatable view.

How do I change the view in MySQL?

To modify a view, you use the ALTER VIEW statement. The syntax of the ALTER VIEW statement is similar to the CREATE VIEW statement except that the CREATE keyword is replaced by the ALTER keyword. The following example changes the organization view by adding the email column.

What triggers SQL?

A SQL trigger is a database object which fires when an event occurs in a database. We can execute a SQL query that will “do something” in a database when a change occurs on a database table such as a record is inserted or updated or deleted. For example, a trigger can be set on a record insert in a database table.

What is difference between stored procedure and function?

The function must return a value but in Stored Procedure it is optional. Even a procedure can return zero or n values. Functions can have only input parameters for it whereas Procedures can have input or output parameters. Functions can be called from Procedure whereas Procedures cannot be called from a Function.