If I create an event in mysql with the interval every day like this:
CREATE EVENT `event`
ON SCHEDULE EVERY '1' DAY ON COMPLETION PRESERVE
ENABLE COMMENT '' DO
UPDATE table SET something = something + 1;
On what time of the day will it execute? I would assume 0AM but the specification does not mention it.
Yes, I am aware that it is possible to specify specific times, however I would like to keep it simple.
Not specifying STARTS is the same as using STARTS
CURRENT_TIMESTAMP—that is, the action specified for the event begins
repeating immediately upon creation of the event.
from the MySQL Reference
Related
DROP EVENT `deleteTestEntries`;
CREATE DEFINER=`root`#`localhost` EVENT `deleteTestEntries`
ON SCHEDULE EVERY 1 MINUTE
STARTS '2018-05-25 18:17:01'
ON COMPLETION NOT PRESERVE ENABLE DO
DELETE FROM lead_master WHERE lead_master.lname LIKE '%Test%'
What is wrong in above event.
It has been created with no errors but not performing any action.
I simply want to delete the records from my lead_master table where lname is 'Test'
Go into my.ini file and add this line,most probably this is the issue.
event_scheduler = on
Restart mysql.Apparently you can even set it on the fly
I finally did it with cron jobs.
I created a controller which calls a model function contains query to delete record.
and set the cron job which calls the controller after specific interval of time.
I am guessing that you don't need an event every minute. Just define a view to filter out the records you don't want:
create view v_lead_master as
select lm.*
from lead_master lm
where lm.lname not like '%Test%';
Then schedule a job or event every day at a slow period to delete the rows you want. Your application should use the view. Your testing should use the base table.
am trying to generate an event that delete a table in a DB
my idea is to make that to run every (saying hypotetically) 10 min for ever ( no end date)
but I get an error as following:
The starts and ends parameters of the create event command are timestamps. Currently the upper limit of timestamp in mysql is 2038-01-19 03:14:07.999999'. You can't specify any ends after this point.
If you want the event to run "forever", then do not specify any ends (although I would be surprised if your application would run unchanged beyond 2038...)
Hi I am quite new to MySQL events and triggers, I have a table called userstatus(userid, timestamp,count, flag) which is used to store data about the user if he's blocked or not. When count reaches 4, the flag becomes 0(blocked). Can you please help me on what I can do to automatically reset the flag to 1 after it remains blocked for an hour.
I have tried the following code:
create event testevent
on schedule
every 1 minute
starts CURRENT_TIMESTAMP
do
update demo.userstatus set flag=1
where timestampdiff(hour,timestamp,CURRENT_TIMESTAMP)>1
This seems to work but is not efficient. Any help would be appreciated. Thanks!
It would be a lot more efficient if you added a datetime field to the usersratus table that contains the date and time until a user is blocked, or use the existing timestamp field that stores when the user was blocked rather than having just a flag.
During login or any activity you deem to fit, you just check if the current time is on or earlier than the block time (or on or before timestamp + 1 hour). If yes, then the user is blocked and you can prevent the activity. If not, then the user is not blocked and can allow the activity. You can even restore the counter at the first successful activity to 1.
This way you avoid the need to periodically check the database and clear the status flag.
I'm creating a database where i want to create a trigger.
This trigger will delete a row if the current time is 5 min over the requesttime in the table.
The requesttime is a datetime attribute in the table.
How can i make a trigger which do this?
You don't want to do this. First, triggers only run when something is happening inside the database (such as an insert or update). They are not the same as scheduled jobs. Second, you generally don't want to do this in a scheduled job. Instead, just create a view:
create view v_table as
select t.*
from table t
where requesttime >= now() - interval 5 minute;
This will return valid requests.
Then, at your leisure, delete the old rows -- if you really need to. There is a good chance you might want to keep them around to know what happened in the past. But you can delete them on Sunday morning at 3:00 a.m. or some other slow time, if you want.
You may want to consider Event Scheduler added in MySQL 5.1.6. Events can be seen as an alternative to Cronjob.
Their main advantages are:
Platform independent; directly written in MySsql
Ability to list all events SELECT * FROM INFORMATION_SCHEMA.EVENTS;
Built in error logging option
Syntax is something similar to:
CREATE EVENT my_event
ON SCHEDULE
EVERY 1 MINUTE
STARTS '2015-01-01 00:15:00'
COMMENT 'Removes forgotten password tokens older thank 1 week.'
DO
DELETE FROM my_table WHERE some_timestamp > NOW();
I am trying to run the MYSQL event at a particular time, and to be repeated after 24 hours:
ALTER EVENT myeventToronto1
ON SCHEDULE EVERY 24 HOUR
STARTS '2013-08-04 02:02:00'
COMMENT 'A sample comment.'
DO
INSERT into `smallworksdb`.`eventtesttable`(ID,NAME) Values(1,'someValue');
When I save the above event, the table is not getting populated at a particular time specified in the event, so I am assuming that the event does not get run.
What am I missing here.
Thanx
Why do I have this string feeling that id is declared as a primary key (or at least unique)? And you are trying to insert the same value every day. The problem would be an error generated by SQL, not that the job is not running.
Typically a field like id would be an auto_increment value that would be set automatically on insert, and not given a particular value.
This is just speculation. There are other possibilities like the scheduler is turned off or the computer reboots at exactly that time every day?