CRC32 will generate a 'unique' value based on the input string, but not as a four digit number ALWAYS. An MD5 encryption generates a 32 digit hex number. I'd guess you'd need to roll your own.
Suggest you look closer in the 'Cleanup Resources' panel. The "pid" won't always show based on the job name, sometimes you have to lookup the job number and then look for an RT_* entry with that number:
Installing a database, MySQL or otherwise, does nothing to DataStage or its ODBC config files. The installation of the "branded ODBC" components all happens when you install the DataStage server.
Yes, hashed records are unique per key field(s) so the trick here is to write the hashed file with enough keys so that your records survive and then use fewer keys when looking up with the UV stage.