The java.sql.PreparedStatement represents a precompiled SQL statement that can be efficiently executed multiple times.

Why is this an issue?

The PreparedStatement is frequently used in loops because it allows to conveniently set parameters. A small optimization is possible by setting constant parameters outside the loop or hard-coding them in the query whenever possible.

What is the potential impact?

Performance: the unnecessary calls to the setter methods bring overhead.
Sustainability: the extra overhead has a negative impact on the environment.

How to fix it

Place calls to setter methods that take a constant argument outside the loop.

Code examples

Noncompliant code example

public class DatabaseExample {

    public record Order(String id, BigDecimal price) {}

    public void updateTodayOrders(Connection connection, List<Order> orders) {
            Date today = java.sql.Date.valueOf(LocalDate.now());
            String insertQuery = "INSERT INTO Order (id, price, executionDate) VALUES (?, ?, ?)";
            PreparedStatement preparedStatement = connection.prepareStatement(insertQuery);

            for(Order order: orders) {
                preparedStatement.setString(1, order.id());
                preparedStatement.setString(2, order.price());
                preparedStatement.setDate(3, today); // Noncompliant
                preparedStatement.executeUpdate();
            }
    }
}

Compliant solution

public class DatabaseExample {

    public record Order(String id, BigDecimal price) {}

    public void updateTodayOrders(Connection connection, List<Order> orders) {
            Date today = java.sql.Date.valueOf(LocalDate.now());
            String insertQuery = "INSERT INTO Order (id, price, executionDate) VALUES (?, ?, ?)";
            PreparedStatement preparedStatement = connection.prepareStatement(insertQuery);

            preparedStatement.setDate(3, today); // Compliant
            for(Order order: orders) {
                preparedStatement.setString(1, order.id());
                preparedStatement.setString(2, order.price());
                preparedStatement.executeUpdate();
            }
    }
}