   LOAD_FILE(file_name)
Reads the file and returns the file contents as a string.  The file
must be located on the server, you must specify the full pathname to the
file, and you must have the FILE privilege.  The file must
be readable by all and be smaller than max_allowed_packet bytes.

If the file doesn't exist or cannot be read because one of the preceding
conditions is not satisfied, the function returns NULL.
