Savepoints allow for partial rollback within a transaction, providing a way to undo part of the transaction without affecting the entire operation.

The two-phase commit protocol is a coordination protocol involving a voting phase and a decision phase to ensure distributed transaction consistency.

Distributed transactions involve multiple participants and a wider scope, whereas local transactions are limited to a single resource or database.

In the context of transaction isolation levels, a 'dirty read' occurs when a transaction reads uncommitted data from another transaction, while a 'non-repeatable read' happens when a transaction reads data committed by another transaction but the data changes before the first transaction completes. Understanding these concepts is crucial in managing data consistency and isolation in concurrent transactions.

The 'rollback' statement in transaction management is used to undo the changes made by the current transaction. If an error occurs or a condition is met, the 'rollback' command ensures that all changes made so far in the transaction are rolled back, maintaining data consistency.

Databases ensure data integrity during concurrent transactions through transactions isolation levels, which define the visibility of changes made by one transaction to other transactions. These levels include Read Uncommitted, Read Committed, Repeatable Read, and Serializable, each providing a different balance between performance and data consistency.

'ACID' stands for Atomicity, Consistency, Isolation, and Durability, which are the key properties ensuring reliable and secure database transactions.

The Two-Phase Commit (2PC) is most appropriate for managing transactions in a distributed system involving updates to multiple databases, ensuring atomicity and consistency across the distributed environment.

The concept of Concurrency Control allows multiple users to make changes to the database concurrently without affecting each other, ensuring data integrity and consistency.

The Serializable isolation level ensures neither dirty reads nor non-repeatable reads, providing the highest level of isolation.

In JDBC, the SQLException is thrown when there is a problem with the SQL syntax.

Using the finally block ensures that resources (like connections, statements, result sets) are closed, even if an SQL exception occurs, promoting proper resource management and avoiding leaks.