SQL UNION OPERATOR

dbconfig.php

<?php

/**
@author : Shubham Maurya,
Email id : [email protected]
**/

$DB_host = "localhost";
$DB_user = "root";
$DB_pass = "";
$DB_name = "union";

 try
 {
     $DBcon = new PDO("mysql:host={$DB_host};dbname={$DB_name}",$DB_user,$DB_pass); 
     $DBcon->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    // echo "Done..";
 }
 catch(PDOException $e)
 {
     echo "ERROR : ".$e->getMessage();
 }
?>

index.php

<?php

/**
@author : Shubham Maurya,
Email id : [email protected]
**/

require_once 'dbconfig.php';

$email="[email protected]";


try 
{
	// UNION
	$stmt=$DBcon->prepare("SELECT name FROM table_1 UNION  SELECT name FROM table_2  ORDER BY name");
	$stmt->execute();
    
    if($stmt->rowcount()>0)
{
	echo "UNION<br><br>";
	while ($row=$stmt->FETCH(PDO::FETCH_ASSOC))
	{
		
		echo "Name : ".$row['name'].'<br>';
	}
}

	// UNION ALL
	$stmt1=$DBcon->prepare("SELECT name FROM table_1 UNION ALL SELECT name FROM table_2  ORDER BY name");
	$stmt1->execute();
    
    if($stmt1->rowcount()>0)
{
	echo "<br>";
	echo "UNION ALL<br> <br>";
	while ($row1=$stmt1->FETCH(PDO::FETCH_ASSOC))
	{
		
		echo "Name : ".$row1['name'].'<br>';
	}
}

	// UNION USING WHERE CLAUSE
	$stmt2=$DBcon->prepare("SELECT name,email FROM table_1 UNION  SELECT name,email FROM table_2 WHERE email=:email");
	$stmt2->execute(array(':email' =>'[email protected]'));
    
    if($stmt2->rowcount()>0)
{
	echo "<br>";
	echo "UNION USING WHERE CLAUSE<br> ";
	while ($row2=$stmt2->FETCH(PDO::FETCH_ASSOC))
	{
		
		echo "<br>name : ".$row2['name'].'<br>';
		echo "email : ".$row2['email'].'<br>';
	}
}

// UNION ALL USING WHERE CLAUSE
	$stmt2=$DBcon->prepare("SELECT name,email FROM table_1 UNION ALL SELECT name,email FROM table_2 WHERE email=:email");
	$stmt2->execute(array(':email' =>'[email protected]'));
    
    if($stmt2->rowcount()>0)
{
	echo "<br>";
	echo "UNION USING WHERE CLAUSE<br> ";
	while ($row2=$stmt2->FETCH(PDO::FETCH_ASSOC))
	{
		
		echo "<br>name : ".$row2['name'].'<br>';
		echo "email : ".$row2['email'].'<br>';
	}
}

} 
catch (PDOException $e) 
{
	 echo $e->getMessage();
}



?>

output.txt

UNION

Name : jack
Name : shubham

UNION ALL

Name : jack
Name : shubham
Name : shubham

UNION USING WHERE CLAUSE

name : jack
email : [email protected] 

name : shubham
email : [email protected]

UNION USING WHERE CLAUSE

name : jack
email : [email protected] 

name : shubham
email : [email protected]

name : shubham
email : [email protected]

union.sql

-- phpMyAdmin SQL Dump
-- version 4.6.5.2
-- https://www.phpmyadmin.net/
--
-- Host: 127.0.0.1
-- Generation Time: Sep 12, 2017 at 08:05 AM
-- Server version: 10.1.21-MariaDB
-- PHP Version: 5.6.30

SET SQL_MODE = "NO_AUTO_VALUE_ON_ZERO";
SET time_zone = "+00:00";


/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
/*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;
/*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */;
/*!40101 SET NAMES utf8mb4 */;

--
-- Database: `union`
--

-- --------------------------------------------------------

--
-- Table structure for table `table_2`
--

CREATE TABLE `table_2` (
  `id` int(11) NOT NULL,
  `name` varchar(255) NOT NULL,
  `email` varchar(255) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

--
-- Dumping data for table `table_2`
--

INSERT INTO `table_2` (`id`, `name`, `email`) VALUES
(1, 'shubham', '[email protected]'),
(2, 'shubham', '[email protected]');

--
-- Indexes for dumped tables
--

--
-- Indexes for table `table_2`
--
ALTER TABLE `table_2`
  ADD PRIMARY KEY (`id`);

--
-- AUTO_INCREMENT for dumped tables
--

--
-- AUTO_INCREMENT for table `table_2`
--
ALTER TABLE `table_2`
  MODIFY `id` int(11) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=3;
/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;
/*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */;
/*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;