What is mysql scheduled stored procedure? how to use?

MySQL scheduled stored procedures: saving you time and improving efficiency

MySQL is a powerful relational database that is widely used in various applications and websites. Stored procedures are a very important feature when using MySQL. It is used to perform predefined operations and can include SQL statements, flow control, and other calculation logic. Scheduled stored procedures are also a common solution in MySQL, which can save time and improve efficiency.

What is a MySQL scheduled stored procedure?

MySQL scheduled stored procedure is a scheduled task that is used to automatically perform specified operations within a specific time interval. They are predefined collections of SQL statements that can be automatically executed within a specified time period. Through scheduled stored procedures, various use cases can be realized, such as:

• Automatic backup of database: to avoid misuse of data or data loss.
• Automatically send emails: Send emails with content such as daily announcements, news summaries, etc.
• Automatically calculate and update data: for example, regularly calculate sales data to determine sales trends and forecast demand in a timely manner.
• Automatically manage data during a specified period: regularly delete expired data, unlock user accounts, etc.

While it is possible to use MySQL events to perform similar tasks, stored procedures are a more flexible solution. It can access the data in the data table and update or delete it as needed.

How to create a MySQL scheduled stored procedure?

To create a MySQL scheduled stored procedure, you need to follow the following steps:

1. Create a stored procedure

Use the CREATE PROCEDURE statement to create a stored procedure. The stored procedure definition should include input and output parameters, operations to execute SQL statements, and other necessary conditions.

Example:

CREATE PROCEDURE procedure_name(IN input1 VARCHAR(20), OUT output1 VARCHAR(50))
BEGIN
-- SQL statement to insert or update data
END

Here, the stored procedure is named procedure_name, which contains an input parameter input1 and an output parameter output1.

2. Specify planned tasks

To specify planned tasks, you can use the CREATE EVENT statement. This statement should include details of the specific scheduled task, such as start execution time, interval, and execution actions.

Example:

CREATE EVENT event_name
ON SCHEDULE EVERY 1 DAY STARTS '2022-01-01 00:00:00'
DO CALL procedure_name('input1', @ output1);

Here, the scheduled task is named event_name. The task is executed once every day, starting from the specified date and time 2022-01-01 00:00:00. The command uses a stored procedure and passes it the parameter "input1". Note how it is set for the output GUI variable, i.e. by using @output1, the @ symbol is used to distinguish that the variable is generated by MySQL during the run.

3. Enable events

Events can be started when using the ALTER EVENT statement.

Example:

ALTER EVENT event_name ON;

4. Start the event scheduler

After successfully creating the scheduled task, you need to set Events are scheduled so that they are executed at regular intervals.

Example:

SET GLOBAL event_scheduler = ON;

Here, "ON" is used to start the scheduler.

Summary

In MySQL, scheduled stored procedures are a very useful function that can help you automatically perform various operations, save time and improve efficiency. Although they require some additional setup and configuration, once configured correctly, they will make the product smarter, more efficient, and more robust over time.

The above is the detailed content of What is mysql scheduled stored procedure? how to use?. For more information, please follow other related articles on the PHP Chinese website!