I have just had a look at this question Location of my.cnf file on macOS and it would have been usefull for me however i have the same problem as one of the commenters (Chris Bartley) who also did an install of MySQL 5.7.19 on Mac OS 10.12 using the .dmg. i think this is the reason for the file not being on my laptop.
But i have a problem with a recursive procedure that sais
Thread stack overrun: 135608 bytes used of a 262144 byte stack, and 128000 bytes needed. Use 'mysqld --thread_stack=#' to specify a bigger stack.
and unfortunately i havent found anywhere on the internet that was able to help.
If i don't have the my.cnf file how do i configure mysql settings like those who do?