mysqli_num_rows generates unlimited amount of data - php

Question

so, I'll try to explain it as good as I can with my knowledge in english.
I am trying to count data from my database, basically - how many fields I have with the same ID. here's image from database.
image from database
for example, in posts i have review system and it works, i have this PHP code to count how many same fields i have with review and id.
Here's the code:
<?php
$revposid = $res['content_id'];
$pos="SELECT review FROM comments WHERE review='positive' and postid=$revposid";
$neg="SELECT review FROM comments WHERE review='negative' and postid=$revposid";
$neu="SELECT review FROM comments WHERE review='neutral' and postid=$revposid";
if ($result=mysqli_query($_db,$pos)){$rowcountpos=mysqli_num_rows($result);}
if ($result=mysqli_query($_db,$neg)){$rowcountneg=mysqli_num_rows($result);}
if ($result=mysqli_query($_db,$neu)){$rowcountneu=mysqli_num_rows($result);}
?>
<div class="reviews" id="reviews">
<span class="good"><b class="fa fa-thumbs-up"></b><?php echo $rowcountpos ?></span>
<span class="neutral"><b class="icon-thumbs-up"></b><?php echo $rowcountneu ?></span>
<span class="bad"><b class="fa fa-thumbs-down"></b><?php echo $rowcountneg ?></span>
</div>
and when I try to use the same code
$revposid = $cont['content_id'];
$pos="SELECT content_id FROM user_content_like WHERE content_id=$revposid";
if ($result=mysqli_query($_db,$pos)){$rowcountpos=mysqli_num_rows($result);}
in my other script I have like system, it should show all my likes and under likes total likes of the post but when I use it it shows unlimited amount of data, i have no idea why. Here's the full code, I would appreciate some help or explanation.
<?php $ususername = $_GET['user_username'];$sql = "SELECT * FROM user_details WHERE user_username='$ususername'";$usresult = mysqli_query($_db,$sql);?>
<?php if( ! mysqli_num_rows($usresult) ) {
echo " Ooops? <br> <br>User <b>".$_GET["user_username"]."</b> doesn't exist.";
} else {
while($usrow = mysqli_fetch_array($usresult,MYSQLI_BOTH)) {?>
<?php
$current_user = $usrow['user_id'];
if ($_db->connect_error) {
die("Connection failed: " . $_db->connect_error);
}
$sql = "SELECT * FROM user_content_like WHERE user_id=$current_user ORDER BY date_added DESC;";
$result = $_db->query($sql);
if ($result->num_rows > 0) {
while($row = $result->fetch_assoc()) {
$content_id = $row['content_id'];
$sql1 = "SELECT * FROM content WHERE content_id=$content_id";
$result1 = $_db->query($sql1);
if ($_SESSION['user_id'] == $usrow['user_id']) {$output = '
<button type="button" class="unlike_button" onclick="unlike(this);" name="like_button" data-content_id="'.$row["content_id"].'" ><i class="fa fa-minus"></i></button>
';} else {
$output = '';
}
while($cont = $result1->fetch_assoc()) {
$revposid = $cont['content_id'];
$pos="SELECT content_id FROM user_content_like WHERE content_id=$revposid";
if ($result=mysqli_query($_db,$pos)){$rowcountpos=mysqli_num_rows($result);}
echo '
<div class="community-feed-thread">
<div class="community-icon-thread"></div>
<div class="community-comments-thread">'.$output.'</div>
<a href="'.$cont["content_id"].'" class="community-title-thread"><h3>'.$cont["title"].'</h3>
<span class="likes-desc"> Total likes: '.$rowcountpos.'</span>
</a>
</div>
';
}
}}
else {
echo " hmmmmmmmmmmmm.<Br><br>". $usrow["user_username"]." doesn't like anything. ";
}
$_db->close();
?>
<?php }}?>
this is how i want it to look
This is how it looks

Answer 1

Your re-using the same variable for different result sets in the code...
$result = $_db->query($sql);
and
if ($result=mysqli_query($_db,$pos))
You will need to ensure you only use the variable name once or it may have side effects in other loops.