Running a MySQL query using a string in php - php

Question

Answer found (syntax): The column name of my string had to be encased in backticks " ` " as they contained spaces. Note that this means that the majority of this post has no relevance to the issue. The code has been corrected in case someone wants to do something similar.
So, I am doing a foreach loop to assign a value (1/0) to non-static columns in my database (it needs to support addition/deletion/editing of columns). I am using $connectionvar->query($queryvar); to do my queries which worked fine up until now when I'm trying to use a custom built string as $queryvar in order to change the column name to a variable within the loop. I've been outputting this string through echo and it looks exactly like my functional queries but somehow doesn't run. I've attempted to use eval() to solve this but to no avail (I feel safe using eval() as the user input is radio buttons).
Here's the loop as well as my thought processes behind the code. If something seems incoherent or just plain stupid, refer to my username.
foreach($rdb as $x) { //$rdb is a variable retrieved from $_POST earlier in the code.
$pieces = explode("qqqppp", $x); //Splits the string in two (column name and value) (this is a workaround to radio buttons only sending 1 value)
$qualname = $pieces[0]; //Column name from exploded string
$qualbool = $pieces[1]; //desired row value from exploded string
$sql = 'UPDATE users SET '; //building the query string
$sql .= '`$qualname`';
$sql .= '=\'$qualbool\' WHERE username=\'$profilename\''; //$profilename is retrieved earlier to keep track of the profile I am editing.
eval("\$sql = \"$sql\";"); //This fills out the variables in the above string.
$conn->query($sql); //Runs the query (works)
echo ' '.$sql.' <br>'; //echoes the query strings on my page, they have the exact same output format as my regular queries have.
}
}}
Here's an example of what the echo of the string looks like:
UPDATE users SET Example Qualification 3='1' WHERE username='Admin2'
For comparison, echoing a similar (working) query variable outside of this loop (for static columns) looks like this:
UPDATE users SET profiletext='qqq' WHERE username='Admin2'
As you can see the string format is definitely as planned, yet somehow doesn't execute. What am I doing wrong?
PS. Yes I did research this to death before posting it, as I have hundreds of other issues since I started web developing a month ago. Somehow this one has left me stumped though, perhaps due to it being a god awful hack that nobody would even consider in the first place.

Answer 1

You need to use backticks when referring to column names which have spaces in them. So your first query from the loop is outputting as this:
UPDATE users SET Example Qualification 3='1' WHERE username='Admin2'
But it should be this:
UPDATE users SET `Example Qualification 3`='1' WHERE username='Admin2'
Change your PHP code to this:
$sql = 'UPDATE users SET `'; // I added an opening backtick around the column name
$sql .= '$qualname`'; // I added a closing backtick around the column name
$sql .= '=\'$qualbool\' WHERE username=\'$profilename\'';

Answer 2

Example Qualification 3 : Is that the name of your Mysql Column name ?
You shouldnt use spaces nor upper / lower case in your columnname.
Prefere : example_qualification_3
EDIT :
To get column name and Comment
SHOW FULL COLUMNS FROM users