using variables ins sprintf word strings

[johng123]

have problems understanding the logic of using variables inside this code. why ist it possible to use %s for different variables and how is it possible to use them as %1$s and %2$s...without even defining them somewhere...i just dont get it, the complete code can be viewed in the thread: hyperlink from url
could anybody help:

$hyperlink = sprintf('%3$s', $url, $target, $showingtext);

// Build the SQL query. This function will again replace each placeholder with the listed variable values respectively
$sql = sprintf("INSERT INTO `hyperlinktable2` SET `url` = '%s', `target` = '%s', `showingtext` = '%s', `hyperlink` = '%s'",
$url, $target, $showingtext, $hyperlink);

here is the form code to the variables

url:
target:
showingtext:

[C#Jaap]

Maybe this will help:

http://nl2.php.net/manual/en/function.sprintf.php

[vibhaJ]

See this example .
In you code you can change %1$s to %1 as all 3 string order is fixed.

echo $hyperlink = sprintf('<a href="http://%s" target="%s">%s</a>', 'url', 'target', 'showingtext');