Apex Trigger insert Tasks to User on Profile Assignment - Error

Question

I am trying to assign tasks to a user based on their profile once the recorded is inserted into Salesforce.

The trigger is hitting an exception even though it's compiling correctly. The code is below:

trigger insertTasks on User (after insert) {
// get list of users needed to assign
List<User> userList = [SELECT Id FROM User where ProfileId = '00e4x000000m2tPAAQ' LIMIT 10];
List<Objectives__c> objList = [SELECT Id FROM Objectives__c];

//loop thru users in the users list created above.
for(User newUser : Trigger.new){
    //create new objectives
    Objectives__c obj = new Objectives__c();
        obj.OwnerId = userList.get(0).Id;
        obj.Status__c = 'Not Started';
}

if(userList.size() > 0)
{
    // insert objectives into a list for the new users with the specified profile
    insert objList;
}

The error is saying that INVALID_FIELD_FOR_INSERT_UPDATE, cannot specify Id in an insert call: [Id]

The goal here is to assign a list of objectives to the new user that gets assigned the correct profile but only if they do not already have any objectives.

Answer 1

There are several problems here.

trigger insertTasks on User (after insert) {
// get list of users needed to assign
List<User> userList = [SELECT Id FROM User where ProfileId = '00e4x000000m2tPAAQ' LIMIT 10];

Never hard-code Ids. Why query 10 users when you only want one? Store the single user Id in a Custom Setting and access it dynamically.

List<Objectives__c> objList = [SELECT Id FROM Objectives__c];

You don't use this; why are you querying it? Unrestricted queries like this can get you into limits trouble very quickly.

//loop thru users in the users list created above.
for(User newUser : Trigger.new){
    //create new objectives
    Objectives__c obj = new Objectives__c();
        obj.OwnerId = userList.get(0).Id;
        obj.Status__c = 'Not Started';
}

You just threw away obj because it was never added to a collection for insert. You probably want to create a new, empty List<Objectives__c> to collect these records.

Also worth noting: these records have no relationship to newUser, so they're not going to be distinguishable from one another when multiple Users are created.

if(userList.size() > 0)
{
    // insert objectives into a list for the new users with the specified profile
    insert objList;
}

1. You don't need to check .size() before performing DML. DML on an empty collection is a no-op.
2. objList is not the correct variable here. That's the spurious List created above that includes every existing Objectives__c record in the database. You want to insert the new collection you create of records built in this trigger.