Requirement:
Move all related Attachments of deceased Contact to either Opportunity or Account record.
If Opportunity is linked then transfer to Opportunity else to Account.
NOTE: Below code will clone the attachments, so once cloning is completed, you can delete old attachments.
This way you will be safe with backup.
Sample Code:
//Source Object: From which we want to transfer attachments
list<Contact> contactList = new list<Contact>();
//Get all the details of Contact where status is deceased and atleast related to Account or Opportunity
contactList = [Select Id,Company__c,Opportunity__c
from Contact
where Status__c = 'Deceased'
AND (Company__c != NULL OR Opportunity__c != NULL)];
//Map to get contact details while iterating over attchment records
map<Id,Contact> contactMap= new map<Id,Contact>(contactList);
//Set to store all contact Ids, which will be used to get all related attachments (you can use keyset of above map as well)
set<Id> contactIds = new set<Id>();
for(Contact con : contactList){
contactIds.add(con.Id);
}
//Get all corresponding attachments of corresponsind Source Object
list<Attachment> allAttchments = new list<Attachment> ();
allAttchments = [Select Id,Name,Body,ParentId
From Attachment
Where ParentId IN :contactIds];
//Final List to insert attchment into new destination object
list<Attachment> allAttchmentsToInsert = new list<Attachment> ();
for(Attachment att : allAttchments){
att.Id = null;
//if Opportunity is not linked then transfer to Related Account
if(contactMap.get(att.ParentId).Opportunity__c == null){
att.ParentId = contactMap.get(att.ParentId).Company__c;
}else{
//if Opportunity is linked then transfer to related Opportunity
att.ParentId = contactMap.get(att.ParentId).Opportunity__c;
}
allAttchmentsToInsert.add(att);
}
//Copy is ready to clone to new target object
if(!allAttchmentsToInsert.isEmpty()){
Insert allAttchmentsToInsert;
}
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