We have created CRON jobs in MySQL where some run daily and some run monthly.
We can see the list of events(jobs) using the following command -
show events from database_name
To identify the execution of an event, logs table was created, and a record was inserted in the logs table whenever an event was executed.
Even though the event is shown as "enabled", the corn job is not getting executed at the set intervals.
Is there a way to identify if the CRON job is properly configured?
Note: We are using MySQL Workbench.
If yes, please share the details.
Thanks in advance!
Related
On Server1, i want to schedule a job (JobTest). I want to schedule this once another job(JobLive) is completed.
Job Live is on Another server (Server2)
How this could be done.
Please respond with your valuable information.
Jobs can only be scheduled to run based on a given time of day. They cannot be scheduled to run based on the completion of another job or any other type of condition.
One way to get what you seem to want to is to have the first job add a record to a table that the second job will have access to, and put a step in the second job to check the table, and if the record is not there in the table, don't do anything. Then you would need to schedule the second job to run throughout a range of time, so that it keeps trying until the record is there in the table. Then when the second job completes, it deletes the record from the table, so that it won't run again until the first job runs again.
I have a database, let's say in MySQL, that logs runs of client programs that connect to the database. When doing a run, the client program will connect to the database, insert a "Run" record with the start timestamp into the "Runs" table, enter its data into other tables for that run, and then update the same record in the "Runs" table with the end timestamp of the run. The end timestamp is NULL until the end of the run.
The problem is that the client program can be interrupted -- someone can hit Ctrl^C, the system can crash, etc. This would leave the end timestamp as NULL; i.e. I couldn't tell the difference between a run that's still ongoing and one that terminated ungracefully at some point.
I wouldn't want to wrap the entire run in a transaction because the runs can take a long time and upload a lot of data, and all of the data from a partial run would be desired. (There will be lots of smaller transactions during the run, however.) I also need to be able to view the data in real-time in another SQL connection as it's being uploaded by a client, so a mega-transaction for the entire run would not be good for that purpose.
During a run, the client will have a continuous session with the SQL server, so it would be nice if there could be a "trigger" or similar functionality on the connection closing that would update the Run record with the ending timestamp. It would also be nice if such a "trigger" could add a status like "completed successfully" vs. "terminated ungracefully" to boot.
Is there a solution for this in MySQL? How about PostgreSQL or any other popular relational database system?
I am using a host gator shared hosting plan, and need to execute a simple command every minute:
UPDATE table_info SET expired = 1 WHERE TIMESTAMP(dateTime) <= NOW()
My problem is that I cant turn on the event scheduler because I don't have permissions for it. Can anyone think of a simple way to do this without using events?
You can put your update statement into simple PHP script, and run it via cron.
Using cron or any other OS based task scheduler is stricktly speaking an answer to this question.
However, it is not really a best practice to run any event every minute. Particularly not, if the operation done could be executed on the fly, like here. The expired flag's value depends on a simple calculation:
dateTime <= NOW()
Instead of running this calculation every minute on the entire table_info, you could
place the sql command into a regularly executed script
just embedd the logic into any reporting or other operation which depend on the expired field and get rid of the flag completely.
I am trying to use mysql event schedule in my application, I have not use it before so i have some confusions.
I want to know if my computer is off on the schedule date, then schedule will continue on next day, after starting my computer?
Like:
my schduled is for beginning at every month (no predefined time set)
if in the above date my computer/Server is off,
will mysql continue scheduled event in next day after turning on my computer/server?
If no, then please suggest a solution.
Hmmmm, have you looked at something like this?
MySQL: Using the Event Scheduler
... or:
How to create MySQL Events
... or even: [MySQL :: MySQL 5.1 Reference Manual: 19.4.1. Event Scheduler Overview](19.4.1. Event Scheduler Overview)?
Also please keep in mind that SQL DBMS servers are written with the rather strong presumption that they will be kept up and operating 24 hours per day with only brief periods of downtime for maintenance or repairs. There is generally very little consideration for operation on machines which are shutdown at night and while not in use.
If you simply store a table of dates and events then your can simply query that table for events which have passed or are upcoming within any range you like ... and you can run the program(s) containing those queries (and performing any appropriate activities based on the results) whenever you start you computer and periodically while it's up and running.
These links refer to a feature of MySQL which is designed to have the server internally execute certain commands (MySQL internal commands, such as re-indexing, creating/updating views, cleaning tables of data which "expires" and so on. I don't know if a MySQL server would attempt to execute all events which have passed during downtime, though it should only be a little bit of work to follow the tutorial, schedule some event for some time (say 15 minutes after the time you expect to hit [Enter]) ... then shutdown your computer (or even just the MySQL server) and go off to lunch. Then come back, start it up and see what happens.
The scheduled event could be something absurdly simple, like inserting the "current" time into some table you set up.
I used a loop in my php script to run insert queries into my db. The loop was looping thousand times. I stop my php script while it was till running. Nevertheless, my db table keeps on getting populated continously. I guess that there must be a queue. but this is only a guess. So I am wondering if I can stop all the pending queries from being executed? Also I am wondering if it is possible to see that queue somewhere? Thank you in advance for your replies. Cheers. Marc.
There is no queue, unless you were using INSERT DELAYED.
You can kill the process that is inserting the data like this:
Run SHOW PROCESSLIST to find the id of the connecton you want to kill
Then run KILL CONNECTION <thread_id> to kill that connection.
SHOW PROCESSLIST will give you a list of all currently running queries