April 2003
Beginner to intermediate
380 pages
12h 25m
English
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Deleting Instances
A persistent-nontransactional instance transitions to
persistent-deleted if it is a parameter of deletePersistent( ).
The values of the fields of the instance in memory are unchanged but are
saved for verification during commit. To minimize the possibility of a
conflict at commit, you can load fresh values from the datastore by
calling refresh( ) or
refreshAll( ) with the
instance as a parameter.
A hollow instance transitions to persistent-deleted if it is a
parameter of deletePersistent( ).
Since there is no state loaded into the instance, the instance will not
be verified during commit. To force verification at commit, you should
first call refresh( ) or refreshAll( ) with the instance as a
parameter.
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.