This code should start looking familiar again. Each time mysql_fetch_row returns
$row, it’s actually returning an array, something you’ve see before (page 46). That
array has all the different pieces of information from your SQL query. For SHOW
TABLES, that’s just one thing, at $row[0]: the table name. Pretty soon, you’ll write
some more complex queries, and you may need to grab the value in $row[1] or
$row[2] or even $row [10].
So in this case, you get back $row, you grab the table name by getting the first item in
the array, at index 0, and then you print that with echo. There’s just one other wrinkle
here: those curly braces inside the string passed to echo. What’s up with those?
Well, you could rewrite this line like this: