Handling SOQL joins in Apex

Question

I want to join 2 tables in a SOQL query. I looked at QueryResult but think it might be a red herring. Difficult to tell from the documentation.

I have a lookup field between table CustomObj and Event. Assuming I have a relationship called Events can I do something like this?

List<CustomObj__c> objects = [Select Id, Name, (Select Id, DataField__c From Events) 
                              From CustomObj__c];

If this works how do I access the fields from the sub query? i.e. can I do this?

objects[0].DataField__c

What happens if the field name of the out query match the field names of the inner query?

Is it easier to forget the join altogether and do 2 queries?

Answer 1

for(CustomObj__c record: objects) {
    for(Event eventRecord: record.Events) {
        // each eventRecord has data
    }
}

You can access them individually as an array, too:

objects[0].Events[0].DataField__c

There will never be a conflict, because the child object will be in its own array.