[PHP/MySQL] Retrieving Data from a Single Row (Error: unknown column)

[generalt]

I have a table with two columns: symbol and company_name. I retrieve the symbol from the url (e.g., .../showco.php?co=RSKIA). Then I want to go to the entry where the symbol matches that in the url (in this case, "RSKIA") and display the name of the company that has that symbol.

$co = $_GET['co'];

	$q = "SELECT * FROM CompanyList WHERE symbol=$co";
	$r = @mysqli_query ($dbc, $q);

	if (mysqli_num_rows($r) == 1) {

		$row = mysqli_fetch_array ($r);

		$company_name = $row[1];

		echo "<h1>" . $company_name . "</h1>";	

	}

I get the following error:

Unknown column 'RSKIA' in 'where clause'

Query: SELECT * FROM CompanyList WHERE symbol=RSKIA

I think this is a pretty basic problem. What am I doing wrong?

[V-Tech]

Change this:

$q = "SELECT * FROM CompanyList WHERE symbol=$co";
[/CODE]

To this:

[CODE]
$q = "SELECT * FROM CompanyList WHERE symbol='$co'";
[/CODE]

[generalt]

Thank you. Problem solved.

[GreenMartian]

Considering the parameter is coming from user input (in this case, freeform URL), you might want to read up on SQL injection and ways to prevent them in PHP.

[Argi]

Ah PHP, I'm so glad I don't have to work with you professional anymore.

Also, mysql_real_escape_string() or read up on prepared statements.