[SOLVED] LEFT JOIN

[MikeDXUNL]

TABLE `achievements`

achid | gameid |    achname      |

1            5        Perfectionist

2            5              5x Eggs

 

TABLE `guides`

guideid | achid | gameid | guidetext

1              1          5          Complete the game, etc etc

2              2          5          Throw 5 Eggs

 

 

<?php
$gameid = $_GET['gameid']; //in this case it is 5

$get_achs = mysql_query("SELECT * FROM achievements LEFT JOIN guides on achievements.achid = guide.achid WHERE achievements.gameid = '$gameid'") or die(mysql_error());

while($ach = mysql_fetch_array($get_achs, MYSQL_ASSOC)) {
echo $ach['guidetext'];
}

?>

 

instead of getting my result, i get:

Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in C:\wamp\www\achunlocked\viewgame.php on line 196

 

Any Help please?

Thanks in advance,

Mike

 

[br0ken]

This might not help but I added a typecast statement to remove the SQL injection risk. Give it a try and tell us if it works. The error you're getting means that the value in $get_achs is not a valid MySQL result set.

 

<?php

$gameid = (int)$_GET['gameid']; // Typecast as int. Remove SQL injection risk

$get_achs = mysql_query("SELECT * FROM achievements LEFT JOIN guides on achievements.achid = guide.achid WHERE achievements.gameid = '$gameid'") or die(mysql_error());

if (mysql_num_rows($get_achs) > 0)
{
while($ach = mysql_fetch_assoc($get_achs)) {
echo $ach['guidetext'];
}
}

?>

[MikeDXUNL]

Unknown column 'guide.achid' in 'on clause'

 

 

 

it was supposed to be guides not guide i found it thanks!

[br0ken]

Congratulations! But please, still take my advise about typecasting.

 

<?php

$gameid = (int)$_GET['gameid']; 

?>

 

By doing this it forces the variable $gameid to contain a number so if a user entered malicious code into this variable in the URL, it would be automatically stripped out. Without this your code is wide open to SQL injection.

 

Please hit the 'Topic Solved' link in the bottom left of this page, if that is all? 

[MikeDXUNL]

my actual $gameid was this

 

 

$gameid = (!isset($_GET['gameid']) || !is_numeric($_GET['gameid']) || $_GET['gameid'] < 1) ? 1 : $_GET['gameid'];

 

 

if put what i did in the post for the purpose of the post

[br0ken]

That's all very confusing. It is much easier to simply typecast it though, you gotta agree?

[MikeDXUNL]

i do. thanks for the heads up