Try changing get_steamid()'s:
Code:
client_print(0,print_chat,"authid %d and id %i inserted into DB",userid,id)
to
Code:
client_print(0,print_chat,"authid %s and id %i inserted into DB",userid,id)
Change was %d to %s.
Do the same for other format() like things. Ex: the SQL line.
Edit: More info in
funcwiki about format().