1. The record is read while another thread is writing it, thus, the
information in the record is simply wrong. So, if my name,
"Javini Javono" was in the database as first name and last name,
then you might read it as "Javini Smith". I would think that you
would definitely never want this kind of read as it is nonsensical.
2. The other type of dirty read would be that the read information
has become stale. Thus, you read in "Javini Javono" but then my
particular physical record was deleted from the database and then
a new record was created with the name "John Smith". Your idea
of what the record holds is out of date. Before updating the record,
you would want to check that the record still refers to "Javini Javono"
and if it does not, you cannot update it, but read the database anew
and display the most current information to the user.
Now gui of NC2 is doubly stale.
When NC2 highlights the stale Bitter Homes record and clicks the Book Button
(the advantage of having fat client )
For my assignment, I looked at all the fields in the record, and if they had
been modified I popped up a dialog box stating which field had been
changed and asking the user if they still wanted to go ahead with the
booking (the advantage of having fat client). But I think this is a bit
beyond the requirements.
I agree with everything you wrote above, *except* (of course ! ) :
What you describe may be performed by a thin/fit client as well.
And BTW, I just read a medical article about fat people : it seems that their life expectancy is at least 10 years shorter.
Thanks for picking that up. I had my triangle around the wrong way. It should have been that the following problems can occur for the given isolation level:I had my triangle around the wrong way :roll:
But it doesn't describe the isolation levels.
This is wrong according to isolation levels described by various RDBMS products: