Accessing Multiple DML Exception Errors from Validation Rules

Question

I've been looking around but haven't found a good explicit answer for handling when multiple validation rules fail simultaneously.

Let's say I have a custom object called MyObject__c with two different validation rules.

The first validation rule will be on a number field called SampleQuantity__c. If SampleQuantity__c < 10, it'll throw an exception saying "Your minimum quantity is 10"

The second validation rule will be on another number field called SampleHoursSpent__c. If SampleHoursSpent__c > 40, it'll throw an exception saying "You have spent the maximum number of hours per week. Please update overtime field."

I'll have something similar to the following when I update my record.

List<MyObject__c> myObjList = getObjects();
try {
      update myObjList;
} catch (DMLException ex) {
    /* this line will get both error messages if both of them fail simultaneously */
    ApexPages.addMessages(ex);

    /* however, if i try to get the number of dml exceptions with a loop,
     * there is only 1 
     */
    for (Integer i = 0; i < ex.getNumDml(); i++) {
        System.debug(ex.getDmlMessage(i));
    }
}

Why can I not see all the DML messages when I try to iterate over them, yet I am able to get them through ApexPages? Shouldn't the behavior be the same?

I've also tried browsing SFDC known issues, but couldn't find something that is related to this issue.

Answer 1

I can presume you are doing multiple updates at a time.

If it is a single update, the first validation error it get captured in catch block and it will not execute again, because of update statement.

I think if you use Database.update() you will get all the DML messages for multiple records which are getting failed.

Database.SaveResult[] update(sObject[] recordsToUpdate, Boolean allOrNone)

allOrNone Type: Boolean

The optional allOrNone parameter specifies whether the operation allows partial success. If you specify false for this parameter and a record fails, the remainder of the DML operation can still succeed. This method returns a result object that can be used to verify which records succeeded, which failed, and why.

Answer 2

@Santanu makes a great point that I would like to expand on a bit. Note in the Database.SaveResult class that there is a getErrors() method that returns a List<Database.Error>. This collection is what you need to iterate through.

Database.SaveResult result = Database.insert(record, /*allOrNone*/ false);
for (Database.Error error : result.getErrors())
{
    // all results will be here
}

Also note that there are different *Result objects depending on your DML operation, but they all share this method.

Database.UpsertResult result = Database.upsert(record, false);
Database.DeleteResult result = Database.delete(record, false);
Database.UndeleteResult result = Database.undelete(record, false);
Database.EmptyRecycleBinResult result = Database.emptyRecycleBin(record, false);