What will happen if concurrency control fails?Lost Update ProblemUncommitted dependency (dirty write) problem / Permanent update problemInconsistency analysis problem / Incorrect summary problemUncommitted dependency (dirty read) problem / Temporary update problemNext

If concurrency control fails, several problems can occur:

1. Lost Update Problem: This occurs when two or more transactions select the same row and update the row based on the value originally selected. Each transaction is unaware of other transactions, so the last update overwrites updates made by the other transactions, which results in "lost updates".

2. Uncommitted Dependency (Dirty Write) Problem: This happens when one transaction updates a database item and then the transaction fails for some reason. The updated item is accessed by another transaction before it is undone. As a result, the second transaction is now dependent on an uncommitted change, which is a problem because the change could be undone, leading to an inconsistent database state.

3. Inconsistency Analysis Problem (Incorrect Summary Problem): This problem occurs when multiple transactions are executing concurrently, and one transaction is calculating an aggregate summary function over a number of records while the other transactions are updating some of these records. The aggregate function may calculate some values before they are updated and others after they are updated.

4. Uncommitted Dependency (Dirty Read) Problem: This problem occurs when one transaction reads data that has been written by another running transaction that has not yet been committed. The data could be rolled back after it has been read, leading to potential inconsistencies.

In summary, the failure of concurrency control can lead to various data integrity issues, causing the database to be in an inconsistent state.