Are there views in MySQL?

Can I create a view in MySQL?

The basic syntax for creating a view in MySQL is as follows: CREATE VIEW [db_name.] … [db_name.] is the name of the database where your view will be created; if not specified, the view will be created in the current database. view_name is a unique name of the view you are creating.

How does MySQL view work?

A view is actually a composition of a table in the form of a predefined SQL query. A view can contain all rows of a table or select rows from a table. A MySQL view can be created from one or many tables which depend on the written MySQL query to create a view.

Are MySQL views permanent?

A view is permanent, but it is a view, not a table. Meaning that it will only execute a sql statement for you in the background each time you access it.

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.

Can you join views in SQL?

Yes, you can JOIN views with tables. You can use views just like tables in SELECTs.

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What is group by in MySQL?

The MYSQL GROUP BY Clause is used to collect data from multiple records and group the result by one or more column. It is generally used in a SELECT statement. You can also use some aggregate functions like COUNT, SUM, MIN, MAX, AVG etc. on the grouped column.

How do I create a trigger in MySQL?

To create a trigger or drop a trigger, use the CREATE TRIGGER or DROP TRIGGER statement, described in Section 13.1. 22, “CREATE TRIGGER Statement”, and Section 13.1. 34, “DROP TRIGGER Statement”. Here is a simple example that associates a trigger with a table, to activate for INSERT operations.

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.

What OS does MySQL run on?

Platform Independence – MySQL runs on over 20 platforms including Linux, Solaris, AIX, HP-UX, Windows, and Mac OS X giving organizations complete flexibility in delivering a solution on the platform of their choice.

How do I view a MySQL database?

Show MySQL Databases

The most common way to get a list of the MySQL databases is by using the mysql client to connect to the MySQL server and run the SHOW DATABASES command. If you haven’t set a password for your MySQL user you can omit the -p switch.

Is Postgres faster than MySQL?

Ultimately, speed will depend on the way you’re using the database. PostgreSQL is known to be faster while handling massive data sets, complicated queries, and read-write operations. Meanwhile, MySQL is known to be faster with read-only commands.

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Are MySQL views cached?

As of mysql 5.1, SELECT queries against the view are cached, therefore any subsequent queries should be quick.

Can we insert and delete rows into a view?

Yes, possible to insert,update and delete to view. view is a virtual table. Same Perform as insert,update,delete query.. A view can be defined as a virtual table or a stored query and the data accessible through a view is not stored in the database as a distinct object.

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