MySQL Array fetch not working - php

Question

I have a WHILE loop to create a set of 4 tabs with tab titles I get from the DB. I also have a field named tab_id (1,2,3,4) inside the DB.
When I run this code the tab_id is "1" for all 4 rows...but the tab titles display correctly. What am I doing wrong?
<?php
while($rows = mysqli_fetch_array($result)){
if ($rows['tab_id'] = 1) { ?>
<li class="active"><a href="#tab<? echo $rows['tab_id']; ?>"
role="tab" data-toggle="tab" ><? echo $rows['tab_title']; ?></a>
</li>
<?php } else { ?>
<li><a href="#tab<? echo $rows['tab_id']; ?>" role="tab" data-
toggle="tab" ><? echo $rows['tab_title']; ?></a></li>
<?php }} ?>

Answer 1

A single = is an assignment operator in php. So php thinks you are saying "Declare $rows['tab_id'] as 1, does 1 loosely evaluate as true?" ...the answer is "yes", so the condition always returns true. (This is the same logic occurring in the while loop on the previous line.)
To make a loose comparison (that is all that is needed) you merely need to add one more = to make ==.
Further advice is that your snippet can be written more D.R.Y. (Don't Repeat Yourself). You are only modifying class="active" so there is no need to rewrite the entire <li> tag.
Suggested code:
while($rows = mysqli_fetch_array($result)){
<li<?php if($rows['tab_id'] == 1) echo ' class="active"'; ?>><a href="#tab<? echo $rows['tab_id']; ?>"
role="tab" data-toggle="tab" ><? echo $rows['tab_title']; ?></a>
</li>
<?php } ?>
or
while($rows = mysqli_fetch_array($result)){
echo "<li",($rows['tab_id'] == 1 ? ' class="active"' : ''),">";
echo "<a href=\"#tab{$rows['tab_id']}\" role=\"tab\" data-toggle=\"tab\" >{$rows['tab_title']}</a>";
echo "</li>";
}

Answer 2

<?php
while($rows = mysqli_fetch_array($result)){
if ($rows['tab_id'] ==1) { ?>
<li class="active"><a href="#tab<? echo $rows['tab_id']; ?>"
role="tab" data-toggle="tab" ><? echo $rows['tab_title']; ?></a>
</li>
<?php } else { ?>
<li><a href="#tab<? echo $rows['tab_id']; ?>" role="tab" data-
toggle="tab" ><? echo $rows['tab_title']; ?></a></li>