正解:B
Understanding the Issue:
The provided code attempts to update a list of Account records:
public static void insertAccounts(List<Account> theseAccounts) {
for(Account thisAccount : theseAccounts) {
if(thisAccount.website == null) {
thisAccount.website = 'https://www.demo.com';
}
}
update theseAccounts;
}
Problem: A DML exception is thrown when the update statement executes.
Possible Causes:
Some records in theseAccounts may have validation rule failures.
There may be null records within the theseAccounts list.
There could be fields that violate data integrity constraints.
Option Analysis:
Option A: Implement Change Data Capture
Modified Code:
public static void insertAccounts(List<Account> theseAccounts) {
for(Account thisAccount : theseAccounts) {
if(thisAccount.website == null) {
thisAccount.website = 'https://www.demo.com';
}
}
try {
update theseAccounts;
} catch (DmlException e) {
// Handle exception, e.g., log error or process partial successes
System.debug('A DML exception occurred: ' + e.getMessage());
}
}
Modified Code:
theseAccounts.removeAll(null);
Reference:
Why Not Suitable: CDC is unrelated to handling exceptions in Apex code. It does not help in gracefully handling DML exceptions.
Option B: Implement a try/catch block for the DML
Apex Developer Guide - Exception Handling
Apex Developer Guide - DmlException Class
Why Suitable:
Graceful Handling: By catching the DmlException, the code can handle the error without abruptly terminating the execution.
Logging and Recovery: Allows the developer to log the exception details and potentially implement recovery logic.
Option C: Implement the upsert DML statement
Why Not Suitable:
The issue is not about distinguishing between insert or update operations.
Using upsert does not inherently handle exceptions; DML exceptions can still occur.
It does not address handling exceptions gracefully.
Option D: Remove null items from the list of Accounts
Why Partially Suitable:
If null records are causing issues, removing them can prevent exceptions.
However, the question specifies a DML exception, not a NullPointerException.
Removing null items does not handle other potential DML exceptions (e.g., validation rule failures).
Conclusion:
Best Solution: Option B is the most appropriate choice.
Wrapping the DML statement in a try/catch block ensures that any exceptions thrown during the DML operation are caught and can be handled gracefully.
This approach aligns with best practices for exception handling in Apex.
Additional Recommendation:
Using Database.update with allOrNone=false:
Database.SaveResult[] results = Database.update(theseAccounts, false);
for (Database.SaveResult sr : results) {
if (!sr.isSuccess()) {
// Handle individual record failure
System.debug('Error updating record: ' + sr.getErrors()[0].getMessage());
}
}
Benefit: Allows partial success processing, handling errors at the record level.