Java & MySQL – Select Records Example
This chapter provides an example on how to select/ fetch records from a table using JDBC application. Before executing the following example, make sure you have the following in place −
-
To execute the following example you can replace the username and password with your actual user name and password.
-
Your MySQL database you are using is up and running.
Required Steps
The following steps are required to create a new Database using JDBC application −
-
Import the packages − Requires that you include the packages containing the JDBC classes needed for database programming. Most often, using import java.sql.* will suffice.
-
Open a connection − Requires using the DriverManager.getConnection() method to create a Connection object, which represents a physical connection with a database server.
-
Execute a query − Requires using an object of type Statement for building and submitting an SQL statement to select (i.e. fetch ) records from a table.
-
Extract Data − Once SQL query is executed, you can fetch records from the table.
-
Clean up the environment − try with resources automatically closes the resources.
Sample Code
Copy and paste the following example in TestApplication.java, compile and run as follows −
import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; public class TestApplication { static final String DB_URL = "jdbc:mysql://localhost/TUTORIALSPOINT"; static final String USER = "guest"; static final String PASS = "guest123"; static final String QUERY = "SELECT id, first, last, age FROM Registration"; public static void main(String[] args) { // Open a connection try(Connection conn = DriverManager.getConnection(DB_URL, USER, PASS); Statement stmt = conn.createStatement(); ResultSet rs = stmt.executeQuery(QUERY); ) { while(rs.next()){ //Display values System.out.print("ID: " + rs.getInt("id")); System.out.print(", Age: " + rs.getInt("age")); System.out.print(", First: " + rs.getString("first")); System.out.println(", Last: " + rs.getString("last")); } } catch (SQLException e) { e.printStackTrace(); } } }
Now let us compile the above example as follows −
C:>javac TestApplication.java C:>
When you run TestApplication, it produces the following result −
C:>java TestApplication ID: 100, Age: 18, First: Zara, Last: Ali ID: 101, Age: 25, First: Mahnaz, Last: Fatma ID: 102, Age: 30, First: Zaid, Last: Khan ID: 103, Age: 28, First: Sumit, Last: Mittal C:>