how to write queries in java
import java.sql.*;
/**
* A Java MySQL SELECT statement example.
* Demonstrates the use of a SQL SELECT statement against a
* MySQL database, called from a Java program.
*
* Created by Alvin Alexander, http://alvinalexander.com
*/
public class JavaMysqlSelectExample
{
public static void main(String[] args)
{
try
{
// create our mysql database connection
String myDriver = "org.gjt.mm.mysql.Driver";
String myUrl = "jdbc:mysql://localhost/test";
Class.forName(myDriver);
Connection conn = DriverManager.getConnection(myUrl, "root", "");
// our SQL SELECT query.
// if you only need a few columns, specify them by name instead of using "*"
String query = "SELECT * FROM users";
// create the java statement
Statement st = conn.createStatement();
// execute the query, and get a java resultset
ResultSet rs = st.executeQuery(query);
// iterate through the java resultset
while (rs.next())
{
int id = rs.getInt("id");
String firstName = rs.getString("first_name");
String lastName = rs.getString("last_name");
Date dateCreated = rs.getDate("date_created");
boolean isAdmin = rs.getBoolean("is_admin");
int numPoints = rs.getInt("num_points");
// print the results
System.out.format("%s, %s, %s, %s, %s, %s\n", id, firstName, lastName, dateCreated, isAdmin, numPoints);
}
st.close();
}
catch (Exception e)
{
System.err.println("Got an exception! ");
System.err.println(e.getMessage());
}
}
}