Locking (was Re: refreshing the GUI)

[Derek Atkins]

Phillip J Shelton <shelton11@dingoblue.net.au> writes:

> Hmm, this is the CVS merge problem isn't it?

Basically, yes.

> Would something like having user A have the only permissions to
> change things if they opened the account first be a usefull first
> pass. Or is that too simple?

How does the UI know whether the user intends to make changes?  I
think this is a rather simplistic view, unfortuately.  You want to
allow multiple people to READ the data at the same time, but you
only want one to be able to WRITE data at a time.

A CVS model is what I was trying to suggest, where two people could
theoretically be changing data at the same time, however the first
person to commit the change will lock the db (thereby serializing the
process) and the second commit will fail because the data was changed
from under it.

> Phill

-derek

-- 
       Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory
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