I need a suggestion on one of apex trigger problem solution - salesforce

Question

I have a custom object "Task Tracking" with 3 custom fields:
1) Lookup to user object.
2) Number of open task (number field)
3) Number if closed task (number field)
When a task is created by user A with let's stay status is IN PROGRESS, I need to create record in Task Tracking object with these details :
1) Lookup field = user A
2) Number of open task = 1
3) Number of closed task = 0;
Now next time, when same user A creates another task, the new Task Tracking record shouldn't be created but it should only update Number of task field.
I have tried this much. I was able to create Task Tracking record whenever a Task is created but It was creating new Task Tracking Object for every Task that I am creating
trigger TrackTask2 on Task (before insert) {
List<sujya__Task_Tracking__c> li = new List<sujya__Task_Tracking__c>();
sujya__Task_Tracking__c s = new sujya__Task_Tracking__c();
if(Trigger.isBefore && Trigger.isInsert){
for(Task t:Trigger.new){
s.sujya__User__c = t.CreatedById;
li.add(s);
}
insert li;
}
}

Answer 1

You should query the system first to see if one exists. If it does, then update it, if it does not then create one.
trigger TrackTask2 on Task (before insert) {
Set<Id> users = new Set<Id>();
for (Task t : Trigger.new) {
users.add(t.ownerId); //might be t.whoId;
}
List<sujya__Task_Tracking__c> existingTrackers = [SELECT Id, sujya__User__c, number_open_task__c, number_closed_task__c FROM sujya__Task_Tracking__c WHERE sujya__User__c IN :users];
Map<Id, sujya__Task_Tracking__c> userTrackerMap = new Map<Id, sujya__Task_Tracking__c>();
for (sujya__Task_Tracking__c tracker : existingTrackers) {
userTrackerMap.put(tracker.sujya__User__c, tracker);
}
for (Task t : Trigger.new) {
sujya__Task_Tracking__c userTracker = existingTrackers.get(t.ownerId);
if (userTracker == null) {
userTracker = new sujya__Task_Tracking__c();
userTracker.number_open_task__c = 1;
userTracker.sujya__User__c = t.ownerId;
} else {
userTracker.number_open_task__c += 1;
}
userTrackerMap.put(userTracker.sujya__User__c, userTracker);
}
upsert userTrackerMap.getValues();
}
This will get you most of the way, but you're going to have to add logic for when a task is closed to decrement the number of open tasks and the number of close tasks.
And please follow trigger best practices by using a handler class