bulk update issue with csv

hi Sir,

It appears there are limits on the csv file size (2M byte) on new listing import or existing listing update. I am faced with importing a sizable quantity of listing somewhat regularly. Breaking down the listings into 2Mb takes considerable amount of time.
I have 2 quick questions:

1) Is the 2Mb limit imposed by geodirectory or my own server settings? Presumably, that can be changed. What are the potential issues if the limit is increased to a higher number (say 10Mbyte)? Will that cause site performance issues?

2) The server is currently run on a dedicated hosting. Presumably, we can update the listing directly to MySQL using SQL script. (There are cases where we need to update one or two fields quickly for many listings.) Are there issues if we update the listing from the backend using SQL script (via database manager, phpmyadmin, etc.)

thanks for your help.

Peter