public static void main(String[] args) {

// Database connection details

String url = "jdbc:postgresql://localhost:5432/java"; // Database URL

String user = "postgres"; // Database username

String pass = "12345"; // Database password

try {

// Step 1: Load PostgreSQL JDBC Driver

Class.forName("org.postgresql.Driver");

// Step 2: Establish connection to database

Connection con = DriverManager.getConnection(url, user, pass);

// Step 3: Create Statement object to execute queries

Statement stmt = con.createStatement();

// Scanner object to take user input

Scanner sc = new Scanner(System.in);

// Taking input from user

System.out.println("Enter ID:");

int id = sc.nextInt();

sc.nextLine(); // Consume leftover newline

System.out.println("Enter NAME:");

String name = sc.nextLine();

System.out.println("Enter ADDRESS:");

String address = sc.nextLine();

System.out.println("Enter CONTACT NO:");

String contact = sc.nextLine();

// Step 4: Create INSERT query using String.format()

String insertQuery = String.format(

"INSERT INTO employees VALUES(%d, '%s', '%s', '%s');",

id, name, address, contact

);

// SELECT query to fetch all records

String selectQuery = "SELECT * FROM employees";

// Step 5: Execute INSERT query

stmt.executeUpdate(insertQuery);

// Step 6: Execute SELECT query

ResultSet rs = stmt.executeQuery(selectQuery);

// Display table header

System.out.println("\nEmployees Details");

System.out.println("ID\tName\tAddress\tContact No");

System.out.println("-------------------------------------------");

// Step 7: Retrieve data from ResultSet

while (rs.next()) {

int Id = rs.getInt("id");

String Name = rs.getString("name");

String Address = rs.getString("address");

String Contact = rs.getString("contact");

System.out.println(Id + "\t" + Name + "\t" + Address + "\t" + Contact);

}

// Step 8: Get ResultSet Metadata (Information about table columns)

ResultSetMetaData resultSetMetaData = rs.getMetaData();

System.out.println("\nColumn Count: " + resultSetMetaData.getColumnCount());

System.out.println("First Column Name: " + resultSetMetaData.getColumnName(1));

System.out.println("First Column Data Type: " + resultSetMetaData.getColumnTypeName(1));

// Step 9: Get Database Metadata (Information about database & driver)

DatabaseMetaData metaData = con.getMetaData();

System.out.println("\nDatabase Product Name: " + metaData.getDatabaseProductName());

System.out.println("Database Product Version: " + metaData.getDatabaseProductVersion());

System.out.println("Driver Name: " + metaData.getDriverName());

System.out.println("Driver Version: " + metaData.getDriverVersion());

// Step 10: Close all resources

rs.close();

stmt.close();

con.close();

sc.close();

} catch (Exception e) {

// Handle exceptions

e.printStackTrace();

}

}