Salesforce PDII Exam Dumps - Actual Questions Answers

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Salesforce uses Database.Savepoint objects to manage transaction integrity, allowing developers to roll back the database state to a specific point in time without aborting the entire transaction. However, savepoints follow a strict "stack" logic.8 When you create savepoints in sequence (SP1, then SP2, then SP3), they exist in a linear timeline.91011

When a developer executes a Database.rollback(SP1), the system reverts the database state to exactly how it was when SP1 was created. A critical side effect of this operation is that any savepoints created after the target savepoint are immediately destroyed and invalidated. Because SP3 was created after SP1,12 rolling back to SP1 clear13s SP3 from the transaction's memory. Therefore, any subsequent attempt to call Database.rollback(SP3) will result in a runtime error because SP3 no longer exists.

To fix this logic, once the code rolls back to SP1 and addresses the condition, it would need to proceed forward through the logic again and potentially set new savepoints if needed. You cannot "jump back forward" to a later savepoint once an earlier one has been invoked, as the rollback has effectively erased the timeline that led to the later savepoints. Understanding this linear invalidation is essential for managing complex nested transactions in Apex.

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In a multi-user environment, a "Race Condition" occurs when two users query the same record at the same time, see that Is_Registered__c is false, and both proceed to update it. To prevent this, developers must implement Row-Level Locking.

In Salesforce SOQL, the FOR UPDATE (Option C) keyword is used for this exact purpose. When a query includes FOR UPDATE, the platform places an exclusive lock on the records returned. If a second transaction attempts to query the same records using FOR UPDATE, it will be forced to wait until the first transaction is completed (either committed or rolled back). If the lock isn't released within 10 seconds, the second transaction throws a QueryException.

By using FOR UPDATE, the first user who executes the query "reserves" the Account. The second user's request will wait, and by the time their query actually executes and retrieves the data, Is_Registered__c will have been updated to true by the first user, thus failing the if (!account.Is_Registered__c) check and preventing a duplicate registration. Option D is a manual "optimistic locking" approach that is less reliable than the platform's native locking mechanism. Options A and B do not address the timing issue of the initial check.

The current bottleneck is caused by the need to resolve Salesforce Internal IDs ($001...$) for the Account lookup before orders can be imported. This can be completely bypassed by using External IDs (Option D) and the Upsert operation (Option C).

External IDs: By marking a unique field from the OMS (like OMS_Account_Number__c) as an External ID in Salesforce, the developer creates a "foreign key" that Salesforce understands.

Upsert Wizard: When using the Data Loader's Upsert wizard, the user is asked which field should be used to match the parent Account. By selecting the OMS_Account_Number__c external ID, the Data Loader allows the user to map the orders directly to accounts using the OMS number found in the CSV file.

Salesforce will automatically find the correct Account ID in the background. This eliminates the "export-and-VLOOKUP" step entirely. Option A (Insert) would still require internal IDs. Option B (sorting) helps with performance in massive loads but doesn't solve the manual ID matching problem. Using Upsert with External IDs is the platform-recommended way to streamline recurring data integrations.