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jdbc mysql example in java

Here’s an example to show you how to connect to MySQL database via a JDBC driver. To connect to MySQL from Java, you have to use the JDBC driver from MySQL. You find the latest MySQL JDBC driver under the following URL:http://dev.mysql.com/downloads/connector/j.
Create a example database and named it test. Now create a a table name it user. Create table user ((userid INT NOT NULL AUTO_INCREMENT,
username VARCHAR(30) NOT NULL,
     PRIMARY KEY (userid));
 
 Now add the record in your table;
 Now create a project in eclipse and mysql-connector jar in its classpath.
package com.test;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
publicclass JavaJDBCExample {
private Connection connect = null;
private Statement statement = null;
private ResultSet resultSet = null;
publicvoid readDatabase()
{
try {
// this will load the MySQL driver
Class.forName("com.mysql.jdbc.Driver");
// setup the connection with the database.
connect = DriverManager
.getConnection("jdbc:mysql://localhost/test?"
+ "user=root&password=admin");
// statements allow to issue SQL queries to the database
statement = connect.createStatement();
// resultSet gets the result of the SQL query
resultSet = statement
.executeQuery("select * from user");
while(resultSet.next()){
//Retrieve by column name
int id = resultSet.getInt("userid");
String username = resultSet.getString("username");
System.out.print("userid: " + id);
System.out.print(", username: " + username+"\n");
}
//STEP 6: Clean-up environment
resultSet.close();
statement.close();
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
connect.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
publicstaticvoid main(String[] args) {
// TODO Auto-generated method stub
new JavaJDBCExample().readDatabase();
}
}

Now run the java file and see the result.

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