Master Hibernate and JPA with Spring Boot in 100 Steps - Step 60 - Understanding Dirty, Phanthom, and Non-Repeatable Rea

The video tutorial explains three key database transaction concepts: dirty read, non-repeatable read, and phantom read. It provides examples to illustrate how these issues arise when transactions run in parallel. Dirty read occurs when a transaction reads uncommitted data from another transaction. Non-repeatable read happens when a transaction reads the same data twice and gets different results due to updates by another transaction. Phantom read involves getting different numbers of rows in repeated queries within a transaction. The tutorial concludes with a brief overview of these concepts and hints at discussing isolation levels in the next session.

What are the three main types of transaction anomalies discussed?

• Dirty read, consistent read, phantom read

• Non-repeatable read, consistent read, phantom read

• Dirty read, non-repeatable read, consistent read

• Dirty read, non-repeatable read, phantom read

In the context of dirty reads, what happens if a transaction fails after modifying data?

• The data is partially committed

• The data remains unchanged

• The data is rolled back to its original state

• The data is committed regardless of the failure

Which anomaly involves reading a modified value before a transaction is committed?

• Consistent read

• Phantom read

• Non-repeatable read

• Dirty read

What is a non-repeatable read?

• Reading different data twice and getting the same result

• Reading different data twice and getting different results

• Reading the same data twice and getting the same result

• Reading the same data twice and getting different results

What causes a non-repeatable read?

• A transaction deleting data

• A transaction inserting new data

• A transaction updating data between reads

• A transaction reading uncommitted data

What is a phantom read?

• Reading committed data

• Reading the same number of rows twice

• Reading uncommitted data

• Reading a different number of rows due to inserts or deletes

How can a phantom read occur?

• By committing data

• By inserting or deleting rows

• By updating data

• By reading uncommitted data