Querying info from one table based on info in another

[weemee500]

Hi, I am currently trying to make a part for my user driven website where one user can subscribe to another and whoever they have subscribed to is echoed back on there profile page.

 

my users table structure is: id    username    password    and my subscription table is:  id    user_id    follow_id

 

i am currently trying to query the logged in users subscriptions with this sql_query

 

$subsQuery = mysql_query("SELECT U.username FROM users AS U INNER JOIN subscription AS Sub.follow_id=U.id WHERE Sub.user_id=".$ID);      $ID being the logged in users id.

 

However when trying to echo this on the page using this bit of php:

 

<? while ($subs = mysql_fetch_assoc($subsQuery)) { ?><br /><br />

<? echo $subs['username'] ?>

 

<?  } ?>

 

it throws back this error:

 

Warning: mysql_fetch_assoc(): supplied argument is not a valid MySQL result resource in /home/avince/public_html/users/user.php on line 53

 

Any help would be much appreciated!

[ILMV]

Simple, your MySQL query is incorrect, could you please echo out your query and post it here.

 

ILMV

[Mark Baker]

Sub isn't automatically an alias for the subscription table unless you define it as such

SELECT U.username 
  FROM users U 
  INNER JOIN subscription Sub AS Sub.follow_id=U.id 
WHERE Sub.user_id=1

 

[ILMV]

Bugger, could you also find the mysql_error description too, after your mysql_query function do this:

 

$subsQuery = mysql_query("SELECT U.username FROM users AS U INNER JOIN subscription AS Sub.follow_id=U.id WHERE Sub.user_id=".$ID)
    or die ("Query '$query' failed with error message: \"" . mysql_error () . '"');

[sasa]

changr to

$subsQuery = mysql_query("SELECT U.username FROM users AS U INNER JOIN subscription AS Sub ON Sub.follow_id=U.id WHERE Sub.user_id=".$ID);