Hi i have trigger on custom object relationship__c which is having a lookup to contacts.

What this trigger does is it checks if an user is having a relationship with the contcat already and if it then it throws an error , it is doing it by checking the Owner field which is automatically populated by default with the created by user.

problem with that is no one else can create a relationship for others because dupes are checked by owner field so instead of the owner field i need to pull the id of the person in the name filed and check it . how can i do that  any ideas?

trigger CheckDupContactRelationShip on Relationship__c (before insert, before update) {

List<Id> contactIds = new List<Id>();
List<Id> ownerIds = new List<Id>();
List<Relationship__c> duplicateContactRels = null;
Map<String,Integer> mapOfDuplicateValues = new Map<String,Integer>();
Integer k = 0;

/*Looping through batch of new records and adding the contactIds and
OwnerIds to individual lists */

for(Relationship__c cr : Trigger.New)
{
contactIds.add(cr.Contact__c);
ownerIds.add(cr.OwnerId);
}

/*Retrieving all the records into a list where the id matches the id
of records that are being inserted or updated*/

duplicateContactRels = [Select id,Contact__c,OwnerId from Relationship__c
where Contact__c in: contactIds and OwnerId in:ownerIds ];

/*If any duplicate records exist adding those to a map to display the error message
In Trigger Insert/Update */
if(duplicateContactRels != null)
{
for(Relationship__c dcr : duplicateContactRels )
{
mapOfDuplicateValues.put(dcr.Contact__c+ ' ' +dcr.OwnerId, k);
k++;
}
}

if(Trigger.isInsert)
{
for (Integer i = 0; i < Trigger.New.size(); i++)
DisplayErrorForDup(i);
}


else if(Trigger.isUpdate)
{
for (Integer i = 0; i < Trigger.New.size(); i++)
{
if(Trigger.Old[i].Contact__c != Trigger.New[i].Contact__c || Trigger.Old[i].OwnerId != Trigger.New[i].OwnerId )
{
DisplayErrorForDup(i);
}
}
}



public void DisplayErrorForDup(Integer j)
{
if(mapOfDuplicateValues.get(Trigger.New[j].Contact__c+ ' ' +Trigger.New[j].OwnerId)!= null)
Trigger.New[j].addError(Label.ConRel_ErrMsgAlreadyExists);
}
}

Thanks 

Akhil