Batch Apex Error

Question

Problem

We are launching a Batch Apex process containing 430 batches (200 records each batch). We've ran it 4 times, all times it finished successfully without any error, but not all batches were processed.

In the "Apex Jobs" section you can see:

• 1° launch: Total Batches: 102 Batches Processed: 102 Failures: 0
• 2° launch: Total Batches: 105 Batches Processed: 105 Failures: 0
• 3° launch: Total Batches: 98 Batches Processed: 98 Failures: 0
• 4° launch: Total Batches: 102 Batches Processed: 102 Failures: 0

The batch process starts showing 430 batches but when it finish shows 105 or less.

Question

Could someone tell us what is going on? Why is SFDC changing the initial batch's amount?

Thank you.

Update

This is the apex code:

ReceiptsBatch Methods

global Database.QueryLocator start(Database.BatchableContext BC){
        this.processStatus = true;

        this.process.Status__c = ProcessManagerUtils.STATUS_INPROGRESS;
        update this.process;

        String query = 'SELECT Id,CloseDate,Amount,Bank_Account_Entity__c,Bank_Account_Formula__c,Credit_Card_Type__c,Credit_Card_Number__c,Credit_Card_Expiration_Month__c,Credit_Card_Expiration_Year__c';
        for (String field : ReceiptsBatchHelper.MAP_KEY_FIELDS){
            query += ','+field;
        }
        query += ' FROM Opportunity WHERE StageName = \''+ReceiptsBatch.PENDING_STATUS+'\''; 
        query += ' AND Payment_Method__c in (\'' + ReceiptTriggerHelper.RECEIPT_PAYMENT_METHOD_AUTO_DEBIT 
                    +'\',\'' + ReceiptTriggerHelper.RECEIPT_PAYMENT_METHOD_CREDIT_CARD + '\')';
        query += ' AND CloseDate <= '+String.valueOf(this.process.Receipts_To_Date__c);
        query += ' AND Receipt__c = NULL';
        query += ' AND AccountId != NULL';

        return Database.getQueryLocator(query);
    }

    global void execute(Database.BatchableContext BC, List<sObject> scope){  
        ReceiptsBatchHelper.myProcessId = process.Id;

        List<Opportunity> donations = (List<Opportunity>) scope;
        try{
            ReceiptsBatchHelper.prepareRemittanceBanks();
            ReceiptsBatchHelper.buildDonorAccountIdByOppIdMap(donations);
            this.receiptsByKeys = ReceiptsBatchHelper.prepareDonationsByGroups( donations, 
                                                                                this.receiptsByKeys );
            ReceiptsBatchHelper.upsertReceiptsAndUpdateOpps(this.receiptsByKeys);
        }
        catch (Exception e){
            this.processStatus = false;
            this.errorDescription = e.getMessage() + '. ' + Label.Line_Info + ' ' + e.getLineNumber();
        }
    }

ReceiptsBatchHelper Methods

public static void prepareRemittanceBanks(){
    for (Bank_Configuration__c conf : [SELECT Bank_code__c, Merchant_Bank__c, Merchant_Bank__r.Concept__c FROM Bank_Configuration__c]){
        remittanceBankByBankEntity.put(conf.Bank_code__c, new Remittance_Bank__c(Id = conf.Merchant_Bank__c, Concept__c = conf.Merchant_Bank__r.Concept__c));
    }
}
public static void buildDonorAccountIdByOppIdMap( List<Opportunity> donations ){
    Map<String, Opportunity> oppMap = new Map<String, Opportunity>();
    for( Opportunity opp : donations ){
        oppMap.put(opp.Id, opp);
    }

    for( OpportunityContactRole ocr : [ SELECT Id, OpportunityId, Contact.AccountId, Contact.Id
                                        FROM OpportunityContactRole 
                                        WHERE OpportunityId IN :oppMap.keySet()
                                        AND Role = 'Donor' AND IsPrimary = TRUE] ){
        donorAccountIdByOppId.put(ocr.OpportunityId, ocr.Contact);
    }
}
public static Map<String, Receipt__c> prepareDonationsByGroups( List<Opportunity> donations, 
                                                                Map<String, Receipt__c> generatedReceiptsMap ){
    for (Opportunity o : donations){
        String key = createKey(o);       

        if (generatedReceiptsMap.containsKey(key)){         
            if(groupedOpportunites.containsKey(key)){       
                groupedOpportunites.get(key).add(o);
            }
            else{
                groupedOpportunites.put(key, new List<Opportunity>{o});
            }
            generatedReceiptsMap.get(key).Amount__c += o.Amount;
            receiptsToUpsert.put(key, generatedReceiptsMap.get(key));
        }else{
            Receipt__c newReceipt = generateReceipt(o);
            groupedOpportunites.put(key, new List<Opportunity>{o});
            receiptsToUpsert.put(key, newReceipt);
            generatedReceiptsMap.put(key, newReceipt);
        }
    }

    return generatedReceiptsMap;
}   
public static void upsertReceiptsAndUpdateOpps (Map<String, Receipt__c> receiptsByKeys ){    
    List<Opportunity> opportunitiesToUpdate = new List<Opportunity>();

    upsert receiptsToUpsert.values();

    for (String key : groupedOpportunites.keySet()){  
        for (Opportunity o : groupedOpportunites.get(key)){
            o.Receipt__c = receiptsByKeys.get(key).Id;
            opportunitiesToUpdate.add(o);
        }
    }

    //if there is an error updating the opportunities, we must delete created receipts
    try{
        update opportunitiesToUpdate;
    }
    catch (Exception e){
        delete receiptsToUpsert.values();

        e.setMessage(Label.Error_linking_opportunities_to_receipts + ' ' + e.getMessage());
        throw e;
    }
}

Answer 1

Turning the comment thread into an answer

The clue here was when you reduced the batch size from 200 to 50 but still stalled out at record 20000. There could be several reasons for this:

1. There is something in the data in the batch processed at record 20,000 - 20,050 that causes the entire batch process to stop. Anything from a Limits error (some sort of out-of-control loop) to an Internal Salesforce Error
2. Or, as you discovered, your Database.Stateful variables exceeded Heap size given that your batch is large (100,000 records). I initially didn't consider this as your code posted didn't include Database.Stateful.