If you are attempting to use a custom relationship, be sure to append the '__r' after the custom relationship name

Question

I'm having trouble putting together a SOQL query.

Basically i have a parent object (Opportunity), with multiple child objects (Borrower_Pair__c). The relationship from the child to parent is created through a master-detail field (Owner_Application__c) on the child (Borrower_Pair__c).

The goal is to get the ids of the all the child objects.

Here is what i have so far...

List<sObject> borrPairIds = [SELECT Id FROM Borrower_Pair__c WHERE Owner_Application__c.Id = :oppId];

Where :oppId is the Id of the opportunity. However when i run this, i get the error in the title.

The full error is

Didn't understand relationship 'Owner_Application__c' in field path. If you are attempting to use a custom relationship, be sure to append the '__r' after the custom relationship name. Please reference your WSDL or the describe call for the appropriate names. (31:37)

Answer 1

Change Owner_Application__c.Id to Owner_Application__c. Alternatively, you could use Owner_Application__r.Id but you should avoid the crossobject reference as it is not necessary.

Answer 2

Owner_Application__c itself represents the Id of Opportunity to which your child object is related to.

You will need to simply use Owner_Application__c in your SOQL:

SELECT Id FROM Borrower_Pair__c WHERE Owner_Application__c = :oppId;