Autofix missing sql functions

Ever since we started using a sql function (civicrm_strip_non_numeric) in 4.3 we have been getting numerous bug reports & support requests, too many to list here. The problem:

• SQL functions have a way of disappearing, esp during db migrations
• Error reporting is very bad - currently a missing sql fn fatals with "unknown error"
• I can't find any other way to strip non-numeric characters from a string using sql

Possible solutions:
a) Autodetect when the fn is missing and autorepair it
b) Stop using sql functions, find another way of stripping non-numeric characters from strings using sql (so far haven't been able to find any other solutions on stack overflow etc)
c) Stop using sql functions, just use php to do it and accept that it will be imperfect. Maybe a cron job to clean up the ones that get missed.
d) Improve error reporting