php mysql multiple field search empty fields - php

Question

<?php
if(isset($_POST['submit'])) {
$fields = array('field1', 'field2', 'field3');
$conditions = array();
foreach($fields as $field){
if(isset($_POST[$field]) && $_POST[$field] != '') {
$conditions[] = "`".$field."` like '%" . mysql_real_escape_string($_POST[$field]) . "%'";
}
}
$query = "SELECT * FROM customer ";
if(count($conditions) > 0) {
$query .= "WHERE " . implode (' AND ', $conditions);
}
$result = mysql_query($query);
$say = mysql_num_rows($result);
if ($say == 0) {
echo "<tr>no result.</tr>";
} else {
echo '...';
while($row = mysql_fetch_array($result))
{
...
}}
} ?>
Why doesn't this code checking empty fields? It returns results that has empty field even form submits empty.

Answer 1

The only improvement I think of is trim():
if(isset($_POST[$field]) && trim($_POST[$field]) != '') {
however, I am sure it is not the issue.
Have you ever thought of printing the resulting query out?
Look, you're writing a program to create some string (SQL query). But for some reason never interested in this program's direct result, judging it by some indirect results. May be it's data/query logic makes such results, but the query itself is okay?
if the query is still wrong - continue debugging.
Echo everything involved - print variables, condition results, intermediate results in the loop - and look for inconsistencies

Answer 2

$query = "SELECT * FROM customer ";
if(count($conditions) > 0) {
$query .= "WHERE " . implode (' AND ', $conditions);
}
When form is submitted empty ($conditions=0) it returns all table (select * from customer).
Added an else condition and fixed. Thanks for print query advices.

Answer 3

For checking something is empty or not. You can use empty() method.
Check this:
empty()
isset() only check whether that object/variable is set or not. For more details check this
isset()