从表中选择值并按时显示？

Question

I want to select values by 'while' but ther is problam, this is the code:

<?php 
$following_select_article = mysql_query("SELECT * FROM follow WHERE user_follower_id='$user_id'");

while( $following_select_article_row = mysql_fetch_array($following_select_article) ) {
    $article_following_user_id = $following_select_article_row['user_following_id'].",";
    $mmnnss = substr_replace($article_following_user_id, "", -1);
    $echo $mmnss;
}

note $user_id = 1

The desired output is

2,3,4

but what I get is

234

The db is like this:

follow table:

id | user_follower_id | user_following_id

1 | 1 | 2

2 | 1 | 4

3 | 1 | 3

thanks

Answer 1

Do This

<?php 

$following_select_article = mysql_query("SELECT * FROM follow WHERE user_follower_id='$user_id'");
$article_following_user_id = "";
while($following_select_article_row = mysql_fetch_array($following_select_article)){

    $article_following_user_id .= $following_select_article_row['user_following_id'].",";

}
$mmnnss = substr_replace($article_following_user_id, "", -1);
echo $mmnnss;

since your substr_replace is in loop so every time after creating $article_following_user_id with , it replace the last character every time

Edit

As suggested by Glavić if you can replace your

substr_replace($article_following_user_id, "", -1);

With

substr($article_following_user_id, 0, -1);