JDBC Transaction Management
Transactions group multiple SQL operations into a single atomic unit. Either all operations succeed (commit) or all are undone (rollback), maintaining data integrity.
Manual Transaction Control
conn.setAutoCommit(false);
try {
debitAccount(conn, fromAccount, amount);
creditAccount(conn, toAccount, amount);
conn.commit();
} catch (SQLException e) {
conn.rollback();
throw e;
} finally {
conn.setAutoCommit(true);
}ACID Properties
- Atomicity — All or nothing.
- Consistency — Database moves from one valid state to another.
- Isolation — Concurrent transactions don't interfere (READ COMMITTED, SERIALIZABLE).
- Durability — Committed data survives system failures.
Isolation Levels
Set with conn.setTransactionIsolation(Connection.TRANSACTION_READ_COMMITTED). Higher isolation prevents more anomalies but reduces concurrency. Most web apps use READ COMMITTED; financial systems may use SERIALIZABLE.
Frequently Asked Questions
Does Spring handle transactions automatically?▼
Yes. @Transactional manages commit/rollback for you. Understanding JDBC transactions helps debug issues and write native SQL code outside Spring.