whart is wrong with this code??? please check

Hi Guys,
I am breaking my head for this error for an hour. Could you help me soon??

The code below is not retriving data from Database.

$course_id = CS100;
$query = 'SELECT * FROM comments WHERE CourseID = "$course_id" ';

But when i try this
$query = 'SELECT * FROM comments WHERE CourseID = "CS100" ';

It is working......

Reply me soon please

 

Variables are not parsed between single quotes. Do it like this:

$course_id = 'CS100';
$query = "SELECT * FROM comments WHERE CourseID = '$course_id'";

PHP:

 

The above is Giving this Syntax Error
Parse error: syntax error, unexpected T_STRING

 

Try this:

[COLOR=#0000ff]$course_id[/COLOR] = [COLOR=#ff0000]'CS100'[/COLOR];
[COLOR=#0000ff]$query[/COLOR] = [COLOR=#ff0000]"SELECT * FROM comments WHERE CourseID = $course_id"[/COLOR];

Code (markup):

 

It is Working as nico_swd said

Thank you very much

Hi babyboy808
I tried that also but was giving the same Error.

Anyhow it is corrected. Thank you

 

just to clarify things up, I think the most right / wise way to do the query is like this..for me, it's more visible to human eyes..

$course_id = CS100;
$query = "SELECT * FROM comments WHERE CourseID = '".$course_id."' ";

PHP: