Hi,
If it it read only, why don't you just import it with load data infile periodically, such as every 30 seconds? Load into new table then swap, just like you would a materialized view. LOAD DATA INFILE handles fixed width files if you do:
LOAD DATA INFILE ... FIELDS DELIMITED BY '';
If the fixed with LOAD DATA INFILE won't work, then just load the file with a delimiter that does not exist in the file, so that all lines are treated as a single value. Use the LOAD DATA ... SET syntax combined with SUBSTR() to extract the columns. It isn't too difficult to make it work, but it might require a little trial and error.
Regards,
--Justin