How to connect to a database using JDBC? Assume that database name is testDb and it has table named employee which has 2 records.
Solution:
Following example uses getConnection, createStatement & executeQuery methods to connect to a database & execute queries.
import java.sql.*;
public class jdbcConn {
public static void main(String[] args) {
try {
Class.forName("org.apache.derby.jdbc.ClientDriver");
}
catch(ClassNotFoundException e) {
System.out.println("Class not found "+ e);
}
System.out.println("JDBC Class found");
int no_of_rows = 0;
try {
Connection con = DriverManager.getConnection
("jdbc:derby://localhost:1527/testDb","username",
"password");
Statement stmt = con.createStatement();
ResultSet rs = stmt.executeQuery
("SELECT * FROM employee");
while (rs.next()) {
no_of_rows++;
}
System.out.println("There are "+ no_of_rows
+ " record in the table");
}
catch(SQLException e){
System.out.println("SQL exception occured" + e);
}
}
}
Result:
The above code sample will produce the following result.The result may vary. You will get ClassNotfound exception if your JDBC driver is not installed properly.