PHP handled MYSQL process questions.

PHP handled MYSQL process questions.

I have an invoicing process that creates 5 tables and fills with with
appropriate data, then builds a 6th final table off of those 5. It is
about 14 queries, I am thinking of using PHP to handle them due to some
date variable needing to be changed.
If I put all 14 in sequence and run it, it works flawlessly. Would you
want to just have the whole sequence in one statement in php? Example
below:
$TheWholeShow = whole sql sequence
$date=$_POST["date"]
mysqli_query($connect,$TheWholeShow)
Or would you want to break it up?
$part1 = build table x
$part2 = build table y
$part... the rest
$date=$_POST["date"]
mysqli_query($connect,$part1,$part2,$part3,$part4..and so on)
I feel this is a hard question to ask without typing a book. Also, I am a
new coder, and am unsure of the proper practices for such.