java - How To Provide Database Independency in JDBC Without Using Hibernate.?

Question

I am trying to solve this problem with the help of properties file, but in a Properties file, we can handle only Database Driver problem. If I want to switch my MySQL to Oracle database I need to change my all query. The problem is how to make query independent in JDBC?

import java.io.FileInputStream;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.Properties;

public class DBIndependencyExample {
    public static void main(String[] args) {
        try {
            Properties pros = new Properties();
            InputStream fis = new FileInputStream(
                    "D:\Programs\Eclipse\DBIndependecyByPropertiesFile\src\connectdb.properties");
            pros.load(fis);
            String Drivername = pros.getProperty("k1");
            //System.out.println(Drivername);
            String url = pros.getProperty("k2");
            String un = pros.getProperty("k3");
            String pw = pros.getProperty("k4");
            Class.forName(Drivername);
            Connection con = DriverManager.getConnection(url, un, pw);
            System.out.println("Driver Is Loaded With" + Drivername);
            System.out.println("Connection is Opened");
            Statement smt = con.createStatement();
            String sql = pros.getProperty("k5");
            //System.out.println(sql);
            ResultSet rs = smt.executeQuery(sql);
            while (rs.next()) {
                System.out.println("username is:" + rs.getString(1) + " password is:" + rs.getString(2));
            }
            con.close();
            System.out.println("Connection is closed");
            fis.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Properties File:

//Mysql Connectivity 
//Start Properties File Code
k1=com.mysql.jdbc.Driver
k2=jdbc:mysql://localhost:3306/practice
k3=root
k4=root
k5=select * from student

//Oracle  Connectivity

k1=oracle.jdbc.driver.OracleDriver
k2=jdbc:oracle:thin:@localhost:1521/orcla
k3=scott
k4=manish       
k5=select * from dept

Answer 1

If i want to switch my mysql to oracle database i need to change my all query.

If your SQL queries rely only on the ANSI SQL and never on proprietary specificites (function, keywords, and...) you should be able to switch from an DBMS to another one without any change in the queries.
Note that Hibernate will not translate for a DBMS specifities to another one as for example translate a query on the DUAL table written in Oracle to a MySQL way.
Hibernate ensures that your SQL queries be portable while you don't create native queries, a possibility still provided by Hibernate.

Here is the original SQL ANSI draft and here a download link for the last version of Information technology -- Database languages -- SQL -- Part 1: Framework (SQL/Framework)