Select numeric characters only from a VARCHAR column without the use of a custom function
I'm importing data to a 3rd party CRM and the restrictions on the phone number field are tighter than those of the source database (MySQL). I would like to grab the first 10 numeric characters in the select. I don't have flexibility to sanitize the existing data. I can only work with what is there. All I can find in forums so far seems to be creating a custom function. Is a custom function the only way? The environment is MySQL 5.7.19.