Session and transaction syntax in MongoDB - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a session in MongoDB?

A session in MongoDB is a context for performing operations that can be grouped together, such as transactions. It helps track and manage these operations consistently.

beginner

How do you start a transaction in MongoDB using a session?

You start a transaction by calling session.startTransaction() after starting a session with client.startSession().

beginner

What is the purpose of commitTransaction() in MongoDB?

The commitTransaction() method finalizes the transaction, making all changes permanent in the database.

beginner

How do you abort a transaction in MongoDB?

You abort a transaction by calling session.abortTransaction(). This cancels all changes made during the transaction.

intermediate

Show the basic syntax to run a transaction in MongoDB using a session.

const session = client.startSession();
try {
  session.startTransaction();
  // Perform database operations here
  await session.commitTransaction();
} catch (error) {
  await session.abortTransaction();
} finally {
  session.endSession();
}

Which method starts a transaction in MongoDB?

A db.transactionStart()

B client.beginTransaction()

C session.startTransaction()

D session.begin()

The correct method to start a transaction in MongoDB is session.startTransaction().

What does commitTransaction() do?

A Cancels the transaction

B Ends the session

C Starts a new transaction

D Makes all transaction changes permanent

commitTransaction() finalizes the transaction and saves all changes.

How do you properly end a session in MongoDB?

A session.close()

B session.endSession()

C client.end()

D db.closeSession()

You end a session by calling session.endSession().

If an error occurs during a transaction, what should you do?

A Call session.abortTransaction()

B Call session.commitTransaction()

C Ignore the error

D Restart the client

You should abort the transaction with session.abortTransaction() to cancel changes.

Which of these is NOT part of MongoDB transaction syntax?

A rollbackTransaction()

B commitTransaction()

C abortTransaction()

D startTransaction()

MongoDB uses abortTransaction() to cancel transactions, not rollbackTransaction().

Explain the steps to perform a transaction in MongoDB using sessions.

Think about how you group multiple operations safely.

Describe what happens when you call abortTransaction() during a MongoDB transaction.

Consider what happens if something goes wrong.