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);
?>
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Output:

Download Source Code

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