JDBC - Viewing a Result Set Example

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Following is the example which makes use of few getInt and getString methods described in Result Set tutorial. This example is very similar to previous example explained in the Navigation Result Set Section.

This sample code has been written based on the environment and database setup done in previous chapters.

Copy and past following example in JDBCExample.java, compile and run as follows:

//STEP 1. Import required packages
import java.sql.*;

public class JDBCExample {
   // JDBC driver name and database URL
   static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";  
   static final String DB_URL = "jdbc:mysql://localhost/EMP";

   //  Database credentials
   static final String USER = "username";
   static final String PASS = "password";
   
public static void main(String[] args) {
   Connection conn = null;
   Statement stmt = null;
   try{
      //STEP 2: Register JDBC driver
      Class.forName("com.mysql.jdbc.Driver");

      //STEP 3: Open a connection
      System.out.println("Connecting to database...");
      conn = DriverManager.getConnection(DB_URL,USER,PASS);

      //STEP 4: Execute a query to create statment with
      // required arguments for RS example.
      System.out.println("Creating statement...");
      stmt = conn.createStatement(
                           ResultSet.TYPE_SCROLL_INSENSITIVE,
                           ResultSet.CONCUR_READ_ONLY);
      String sql;
      sql = "SELECT id, first, last, age FROM Employees";
      ResultSet rs = stmt.executeQuery(sql);

      // Move cursor to the last row.
      System.out.println("Moving cursor to the last...");
      rs.last();
      
      //STEP 5: Extract data from result set
      System.out.println("Displaying record...");
      //Retrieve by column name
      int id  = rs.getInt("id");
      int age = rs.getInt("age");
      String first = rs.getString("first");
      String last = rs.getString("last");
  
      //Display values
      System.out.print("ID: " + id);
      System.out.print(", Age: " + age);
      System.out.print(", First: " + first);
      System.out.println(", Last: " + last);

      // Move cursor to the first row.
      System.out.println("Moving cursor to the first row...");
      rs.first();
      
      //STEP 6: Extract data from result set
      System.out.println("Displaying record...");
      //Retrieve by column name
      id  = rs.getInt("id");
      age = rs.getInt("age");
      first = rs.getString("first");
      last = rs.getString("last");
  
      //Display values
      System.out.print("ID: " + id);
      System.out.print(", Age: " + age);
      System.out.print(", First: " + first);
      System.out.println(", Last: " + last);
     // Move cursor to the first row.

      System.out.println("Moving cursor to the next row...");
      rs.next();
      
      //STEP 7: Extract data from result set
      System.out.println("Displaying record...");
      id  = rs.getInt("id");
      age = rs.getInt("age");
      first = rs.getString("first");
      last = rs.getString("last");
  
      //Display values
      System.out.print("ID: " + id);
      System.out.print(", Age: " + age);
      System.out.print(", First: " + first);
      System.out.println(", Last: " + last);

      //STEP 8: Clean-up environment
      rs.close();
      stmt.close();
      conn.close();
   }catch(SQLException se){
      //Handle errors for JDBC
      se.printStackTrace();
   }catch(Exception e){
      //Handle errors for Class.forName
      e.printStackTrace();
   }finally{
      //finally block used to close resources
      try{
         if(stmt!=null)
            stmt.close();
      }catch(SQLException se2){
      }// nothing we can do
      try{
         if(conn!=null)
            conn.close();
      }catch(SQLException se){
         se.printStackTrace();
      }//end finally try
   }//end try
   System.out.println("Goodbye!");
}//end main
}//end JDBCExample

Now let us compile above example as follows:

C:\>javac JDBCExample.java
C:\>

When you run JDBCExample, it produces following result:

C:\>java JDBCExample
Connecting to database...
Creating statement...
Moving cursor to the last...
Displaying record...
ID: 103, Age: 30, First: Sumit, Last: Mittal
Moving cursor to the first row...
Displaying record...
ID: 100, Age: 18, First: Zara, Last: Ali
Moving cursor to the next row...
Displaying record...
ID: 101, Age: 25, First: Mahnaz, Last: Fatma
Goodbye!
C:\>


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