I get this error:
Fatal error: Call to undefined function: mysql_real_escape_string()

Why? The site works fine on my local database. The only thing I can think of is the version - locally I have v3.23.49 and my host has
v3.23.39. I cannot tell from the online docs when this function was included (a MAJOR failure in the docs imo).

I'll use mysql_escape_string() if I have to but again, I cannot tell which version of mySQL it was introduced in.