PHP SQL Left Join

JOIN is used to query data from two or more tables. The left join is used in case of need to return all rows from the left table, even if the right table doesn't have any match.

PHP SQL Left Join

PHP SQL Left Join

     

This Example illustrates how to use left join clause in the sql query. 

JOIN is used to query data from two or more tables. The left join is used in case of need to return all rows from the left table, even if the right table doesn't have any match. In this example left join is used to join the two table data according to the emp_id field of "emp" table. We are using "emp", "message" tables in the example. We will find the name from emp table and messages from message table where emp_id in both tables are equal. The fetched result is  displayed on the browser as below and the complete source code is available below for download or copy the code as per your need.

 

 

 

 

Table: emp

Table: Message

Source Code of leftJoin.php

<?php
  $con = mysql_connect("localhost","root","root");
  if (!$con) {
  die('Could not connect: ' . mysql_error());
  }

  mysql_select_db("test", $con);
  $result = mysql_query("SELECT emp.name, message.messages FROM  emp LEFT JOIN message ON emp.emp_id = message.emp_id");

  echo "<table border='1'>
  <tr>
  <th>Name</th>
  <th>Message</th>
  </tr>";
  while ($row = mysql_fetch_array($result)) {
  echo "<tr>";
  echo "<td>" . $row['name'] "</td>";
  echo "<td>" . $row['messages'] "</td>";
  echo "</tr>";
  }
  echo "</table>";
  
  mysql_close($con);
?>

 

Output:

 

Download Source Code