trying to use $_POST[‘var’] in a query, as text

i’m having trouble with the code below. it’s been simplified to show the problem. i use a loop because the input names are identical and need to create multiple new rows in a mysql table. the problem is i’m using $_POST[‘name’][$i] and the table won’t accept because it doesn’t see it as ‘text?, …i think.
like i said, code’s been greatly simplified.

for($i=0;$i<count($_POST[‘url’]); $i++) {
$sql = ‘INSERT INTO urls (url) VALUES (‘. $_POST[‘url’][$i].’)’;
if(!mysql_query($sql)) {
echo “error ” . mysql_error();
}
}

i tried to rememdy with this –
$sql = ‘INSERT INTO urls (url) VALUES (‘. ‘”‘. $_POST[‘url’][$i].'”‘. ‘)’;

if i do this it works, there is no error
$sql = ‘INSERT INTO urls (url) VALUES (‘ ” hello ” ‘)’;

this is probably a newbie type mistake, right? thanks for any help with this.

Also in #PHP _↴