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Working with Result Sets

When retrieving data from a database using JDBC, the data is typically returned as a result set. A result set is a table-like structure that contains the rows and columns of the data fetched from the database.

To work with result sets in JDBC, you need to perform the following steps:

Execute a statement or a prepared statement that queries the database.
Obtain the result set object by calling the executeQuery method.
Iterate over the result set using a loop and process the data in each row.
Close the result set object after you're done.

Here's an example of retrieving data from a result set in JDBC:

TEXT/X-JAVA

1import java.sql.Connection;
2import java.sql.DriverManager;
3import java.sql.PreparedStatement;
4import java.sql.ResultSet;
5
6public class Main {
7    public static void main(String[] args) {
8        // Replace with your database URL, username, and password
9        String url = "jdbc:mysql://localhost:3306/mydatabase";
10        String username = "root";
11        String password = "password";
12
13        try {
14            // Establish a connection to the database
15            Connection connection = DriverManager.getConnection(url, username, password);
16
17            // Create a statement
18            String query = "SELECT * FROM employees";
19            PreparedStatement statement = connection.prepareStatement(query);
20
21            // Execute the query
22            ResultSet resultSet = statement.executeQuery();
23
24            // Process the result set
25            while (resultSet.next()) {
26                int id = resultSet.getInt("id");
27                String name = resultSet.getString("name");
28                int age = resultSet.getInt("age");
29
30                System.out.println("Employee ID: " + id);
31                System.out.println("Employee Name: " + name);
32                System.out.println("Employee Age: " + age);
33                System.out.println();
34            }
35
36            // Close the result set
37            resultSet.close();
38
39            // Close the statement
40            statement.close();
41
42            // Close the connection
43            connection.close();
44        } catch (Exception e) {
45            // Handle the exception
46            System.out.println("Error executing query: " + e.getMessage());
47        }
48    }
49}

xxxxxxxxxx
}
 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
​
public class Main {
    public static void main(String[] args) {
        // Replace with your database URL, username, and password
        String url = "jdbc:mysql://localhost:3306/mydatabase";
        String username = "root";
        String password = "password";
​
        try {
            // Establish a connection to the database
            Connection connection = DriverManager.getConnection(url, username, password);
​
            // Create a statement
            String query = "SELECT * FROM employees";
            PreparedStatement statement = connection.prepareStatement(query);
​
            // Execute the query
            ResultSet resultSet = statement.executeQuery();
​
            // Process the result set
            while (resultSet.next()) {
                int id = resultSet.getInt("id");
                String name = resultSet.getString("name");
                int age = resultSet.getInt("age");
​

Working with Result Sets

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