Question

I have a string that looks like this:

"count( IF (my_id = 'mykey',value,100)) mykey"

However, the value ‘mykey’ that goes right after my_id is in a variable called $which_value;

I fail to see how I can put the $which_value so that it mantains the single quote around it.

Answer 1

Just add the variable inside your string:

"count( IF (my_id = '$which_value',value,100)) mykey"

You should, however, escape the value properly or use prepared statements:

$stmt = $db->prepare("SELECT count(IF (my_id = :my_value, value, 100)) mykey...");

$stmt->execute(array(
    ':my_value' => $which_value,
));

Or, using plain ol’ mysql_ functions:

$sql = sprintf("SELECT count(IF(my_id = '%s', value, 100)) mykey...", 
    mysql_real_escape_string($which_value)
);
mysql_query($sql);