#jdbc code explainers

java

public class AccountRepository {
 
    private final DataSource dataSource;

Optimistic locking with a version column in JDBC

optimistic-locking jdbc concurrency

Intermediate 8 steps

java

public List<User> findUsersByEmailDomain(String domain, int minAge) {
    String sql = """
        SELECT id, username, email, age, created_at
        FROM users

Safe parameterized JDBC queries in Java

jdbc sql-injection prepared-statement

Intermediate 7 steps

java

public List<OrderSummary> streamRecentOrders(LocalDateTime since, Consumer<OrderSummary> handler) {
    String sql = """
        SELECT id, customer_id, total_cents, status, created_at
        FROM orders

Streaming large JDBC result sets safely

jdbc streaming resource-management

Intermediate 7 steps

java

public class KeysetPaginationRepository {
 
    private final DataSource dataSource;

How keyset pagination works in Java

pagination sql jdbc

Intermediate 8 steps

java

public class OrderRepository {
 
    private static final int BATCH_SIZE = 500;
    private static final String INSERT_SQL =

Batched JDBC inserts with transaction safety

jdbc batching transactions

Intermediate 8 steps