https://www.ldraw.org/part-number-spec.html under "Patterned Part Code" has a list of themes and their respective digits.
But as Orion stated, that list is quite old and a bit outdated...
(we can use it if possible, but if a letter is already full we can just use any free letters, as long it follows the pXX, and if this is also full, extend it to pXXXX)
and your part (87079p0r.dat) isnt that specific to star wars (prX or psX), its rather geometric, so the p0r is ok.
But as Orion stated, that list is quite old and a bit outdated...
(we can use it if possible, but if a letter is already full we can just use any free letters, as long it follows the pXX, and if this is also full, extend it to pXXXX)
and your part (87079p0r.dat) isnt that specific to star wars (prX or psX), its rather geometric, so the p0r is ok.