Hi Friends,

Scenario: Object A has two contact look up fields.I want  to update the first look up field from  a look up field available on the second look up field.I have accomplished this via a trigger.But I came across something which totally blew away my mind.

I want to populate MasterContactrecord__c field of object A from a look up field Master_Contact_Record__c available on the another lookup on object A -  Opportunity_Contact__c.



Trigger 1: runs successfully and accomplishes the requirement
******************
trigger populate1 on A (before insert,before update) {

Set<Id> set_OpportunityContactIDs = new Set<Id>();

For(A ocr : trigger.new)

if(ocr.Opportunity_Contact__c!=null)
{
set_OpportunityContactIDs.add(ocr.Opportunity_Contact__c);
}

Map<Id,Contact> map_MasterContactRecord = new Map<Id,Contact>
    (   [   SELECT  Master_Contact_Record__c
            FROM    Contact
            WHERE   Id IN :set_OpportunityContactIDs
        ]
    );
    
    
for ( A ocr1: trigger.new )
    {
        if(ocr1.Opportunity_Contact__c!=null)
        ocr1.MasterContactrecord__c = map_MasterContactRecord.get( ocr1.Opportunity_Contact__c ).Master_Contact_Record__c;
    }
}
********************
Trigger 2:Saves succesfully but doesn't work.Why?if I used the same relationship  I used here in quey editor,it returns the exact record I want.
trigger populate on A (before insert,before update) {

For(A ocr : trigger.new)
{
if(ocr.Opportunity_Contact__r.Master_Contact_Record__c!=null)
{
ocr.MasterContactrecord__c=ocr.Opportunity_Contact__r.Master_Contact_Record__c;
//ocr.MasterContactrecord__c=ocr.Opportunity_Contact__r.Master_Contact_Record__r.Id; This seem correct but doesn't return anything in quey editor.
}

}

} 

Is there something I am missing.Pointing to any mistake is highly appreciable!!