I am looking for help on an issue with NHibernate which has been bugging me for a while now. Long story short:
I’m looking for a way to, in the first level cache, “reset” a property on an entity each time I do an update or an insert.
What I want to achieve is that the property in question will always be considered to be dirty by NHibernate when using dynamic update or insert.
The backstory for this is that I know that, if the transaction was successful, the column that I want to “reset” will be set to Null in the database by a trigger. On the flip side, the first level cache does not know this, and thus NHibernate will think that the property was not updated when I set it to the same value as I did on the previous update/insert. The catch is that my trigger is dependent on this value being set. The resulting mess is that if I want to use dynamic update or insert I’m only able to update/insert an entity once without “refreshing” it afterwards (which I really don’t want to do).
Tips or help would be much appreciated, because I’ve really hit a wall here
NHibernate provides many places for extension. Among them is the Session
IInterceptor
. There is documentation with many details:http://nhibernate.info/doc/nh/en/index.html#objectstate-interceptors
In this case, we can create our custom one, which will be observing our entity (for example Client) and a property which must be updated every time (for example Code). So our implementation could look like this:
NOTE: This is just an example! Apply your own logic for checking the dirty properties.
And we have to wrap
Session
this way:And this is it. While Client is marked as dynamic-update, the property Code will always be set as dirty