Collapse all process instances in only one instance

Hi ,

I have a sub-process that inserts the users waiting for OHS Training session in a mysql database. And when it is available a new OHS training session the OHS trainer should send an email to all users waiting for OHS Training.

"Waiting for OHS Training" --> Inserts users' data in the database; "Get Users Waiting" --> mysql connector that returns all emails of users waiting for training "New OHS Training Notification" --> shows a form with all users' emails , message, subject ... "Send OHS Training Notification" --> email connector , send an email to all users waiting.

My problem is that the OHS trainer will get as much process instances as the number of users that apply for OHS Training and I want that the trainer only gets one process instance that sends an email to all users inserted in the database.

In other words , I want that "New OHS Training Notification" and "Send OHS Training Notification" only have one instance, other wise, for each process instance that the OHS Trainer performs all users will receive an notification email.

If there are 10 users waiting , in my current version of this sub-process, the OHS Trainer will have 10 process instances, and the OHS Trainer will have to perform all of them and each user will receive 10 repetead emails when they only should receive one.

After those two tasks ("New OHS Training Notification" and "Send OHS Training Notification") all process instances should be available again.

Has anyone had a problem like this ? Or know how to fix it ?

Greetings, João