How do MySQL events work?
MySQL events are tasks that are executed according to a schedule. Therefore, we sometimes refer to them as scheduled events. When you create an event, you are creating a named database object that contains one or more SQL statements to be executed at one or more regular intervals, starting and ending at a specific date and time.
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How can I see what events are running in MySQL?
SELECT * FROM OUTLINE_INFORMATION. events; You can also use SHOW CREATE EVENT yourevent to see what it does.
How do I run a MySQL event scheduler?
To enable the Event Scheduler, restart the server without the command line option –event-scheduler=DISABLED, or after removing or commenting out the line containing event-scheduler=DISABLED in the server configuration file, as appropriate.
Does MySQL have a scheduler?
MySQL Event Scheduler manages the scheduling and execution of events, that is, tasks that are executed according to a schedule. 6, “MySQL Privileges and Event Scheduler,” discusses the privileges required to work with events and the ramifications events have with respect to privileges when they are executed.
What are triggers in 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 called automatically in response to an event. Each trigger is associated with a table, which is fired on any DML statement, such as INSERT, UPDATE, or DELETE.
How do I activate a MySQL database?
How to create triggers in MySQL?
- CREATE TRIGGER trigger_name.
- (AFTER | BEFORE) (INSERT | UPDATE | DELETE)
- IN table_name FOR EACH ROW.
- START.
- –variable declarations.
- –fire code.
- FINAL;
Why are MySQL events called scheduled events?
Therefore, MySQL events are sometimes called scheduled events. MySQL events are named objects that contain one or more SQL statements. They are stored in the database and run at one or more intervals. For example, you can create an event that optimizes all tables in the database that runs at 1:00 am every Sunday.
What happens when a client connects to a MySQL server?
Connections correspond to Sessions in standard SQL terminology. A client connects to the MySQL server and remains connected until disconnected. Figure 1 illustrates what happens when a MySQL client connects to a MySQL server. Clientele.
Why is MySQL running on a busy connection?
It will mainly depend on two things, the client load and the hardware MySQL is running on. A connection can be more or less busy. A connection is very busy when the client sends consecutive queries to the server, that is, every time the client gets a result, it immediately sends a new query to the server.
What happens when the client disconnects from the MySQL server?
Figure 3 illustrates what happens when a MySQL client disconnects from a MySQL server. The Client sends a COM_QUIT command which causes the server to close the socket. A disconnect can also occur when either side closes its end of the socket.