Transaction performance considerations in MongoDB - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to start a transaction in MongoDB.

MongoDB

const session = client.startSession();
session.[1]();

Drag options to blanks, or click blank then click option'

AinitTransaction

BbeginTransaction

CstartTransaction

DopenTransaction

Attempts:

3 left

💡 Hint

Common Mistakes

Using a method name that does not exist like 'beginTransaction'.

Confusing session start with client start.

In MongoDB, startTransaction() is the correct method to begin a transaction within a session.

2fill in blank

medium

Complete the code to commit a transaction in MongoDB.

MongoDB

await session.[1]();

Drag options to blanks, or click blank then click option'

Acommit

BsaveTransaction

CfinalizeTransaction

DcommitTransaction

Attempts:

3 left

💡 Hint

Common Mistakes

Using just 'commit' which is not a method.

Using 'saveTransaction' which does not exist.

The correct method to commit a transaction in MongoDB is commitTransaction().

3fill in blank

hard

Fix the error in the code to abort a transaction properly.

MongoDB

await session.[1]();

Drag options to blanks, or click blank then click option'

AabortTransaction

BrollbackTransaction

CstopTransaction

DcancelTransaction

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'rollbackTransaction' which is not a MongoDB method.

Using 'cancelTransaction' which does not exist.

The correct method to abort a transaction in MongoDB is abortTransaction().

4fill in blank

hard

Fill both blanks to set transaction options for read concern and write concern.

MongoDB

const transactionOptions = {
  readConcern: { level: '[1]' },
  writeConcern: { w: '[2]' }
};

Drag options to blanks, or click blank then click option'

Amajority

Blocal

C1

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'majority' for read concern which can slow performance.

Using write concern '0' which does not wait for acknowledgment.

Setting readConcern to 'local' and writeConcern to '1' is a common way to balance performance and consistency.

5fill in blank

hard

Fill all three blanks to create a transaction with options and start it.

MongoDB

const session = client.startSession();
const options = { readConcern: { level: '[1]' }, writeConcern: { w: '[2]' } };
session.[3](options);

Drag options to blanks, or click blank then click option'

Amajority

B1

CstartTransaction

Dlocal

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'local' instead of 'majority' for read concern here.

Forgetting to pass options to startTransaction.

This code sets readConcern to 'majority', writeConcern to '1', and starts the transaction with startTransaction().