How to get ID from Parent object when field value matches

Question

I have a requirement to update Account_Transfer__c(Child) object with District Name(Parent) when a field value matches on child record.

below is the logic that I've achieved so far

   insert accTransferPolicy; //inserting Account Transfer Policy record (grand child)
    Map<string, District__c> mapATwithDistrict = new Map<string, District__c>();
    for (District__c dst : [
            SELECT id, Name
            FROM District__c
            WHERE Status__c = 'OPEN' ]) {
            mapATwithDistrict.put(dst.Name, dst);
        }
    for (Account_Transfer_Policy__c c : accTransferPolicy) {
        if (c.Account_Transfer__c != null) {
            if (mapATwithDistrict.containsKey(c.Account_Transfer__r.District_From__c)) {
                    c.Account_Transfer__r.Transfer_From__c = mapATwithDistrict.get(Name).Id;
                }
        }            
        update c;
    }

From the above code, the hierarchy is as:

Account_Transfer_Policy (grand child) --> Account_Transfer__c (Child) --> District__c (Parent)

Now, from the above code, i'm getting the error as

Variable does not exist: Name

can anyone please let me know on how to update Transfer_From__c field with matching district Name Id when District name on District__c record and District_From__c on Account Transfer record matches

Answer 1

SK_112,

Since you're assigning the District's Name as the key for mapATwithDistrict Map, you'll need to use the name to retrieve the Id.

Change From:

if (mapATwithDistrict.containsKey(c.Account_Transfer__r.District_From__c)) {
                c.Account_Transfer__r.Transfer_From__c = mapATwithDistrict.get(<How to get matching district id>).Id;
            }

Change To:

if (mapATwithDistrict.containsKey(c.Account_Transfer__r.**District__r.Name**)) {
                c.Account_Transfer__r.Transfer_From__c = mapATwithDistrict.get(c.Account_Transfer__r.**District__r.Name**).Id;
            }