I am fed up of people asking me how to make Database connections in Java . No one wants to go through the painfull part of studying themselves . All they want is the short-cut . So let me dedicate this particular posts to the topic of database connections in Java .
I have MySQL 5.0 installed on my Windows. In order to make a JDBC connection to MySQL database one needs to downlad the MySQL/J connector driver from here . I will also expect that you have Netbeans 6+ installed on your machine.
Extract the zip file to a folder, you’ll see file ‘mysql-connector-java-5.0.6-bin.jar’ which is the library file that we want. Just copy the file to the library folder, for example to “C:\Program Files\Java\jdk1.6.0_02\lib” also to the "C:\Program Files\Java\jdk1.6.0_02\jre\lib directory.
Next, create a new Java project on NetBeans named ‘TestMySQL’.
Now I’m going to write some code to connect to MySQL database. I have configured MySQL service on localhost.
I’m going to use Connection and DriverMapper Classes so I need to import libraries.
import java.sql.*;
Inorder to test my connections I build my project.
So everything seems to be fine till now.
To get some data, I need to execute query on the SQL Server and get the result back to me. First, I create stmt (Statement object) and execute query in SQL language. Then I store the result on ResultSet object and iterative show the result on the output window.
Insert some data to the created table using the code
Statement stmt = null;
stmt = con.createStatement();
String SQL = "INSERT INTO ZanduBaam (Name,Roll) VALUES ('Abhishek',40)";
int rowsEffected = stmt.executeUpdate(SQL);
System.out.println(rowsEffected + " rows effected");
Inorder to retrieve data from database , I need to execute query on the SQL Server and get the result back to me. First, I created stmt (Statement object) and execute query in SQL language. Then I store the result on ResultSet object and iterative show the result on the output window.
ResultSet rs = null; // SQL query command String SQL = "SELECT * FROM ZanduBaam"; stmt = con.createStatement(); rs = stmt.executeQuery(SQL); while (rs.next()) {
System.out.println(rs.getString("Name") + " : " + rs.getString("Roll"));
}