Question

I am trying to run the following detached criteria query:

    def e = new DetachedCriteria(Equipment).build {
        eq('name', ef.name)
    }.get()

but when I call e.isAttached() immediately afterward, I get true.

Background: I know I have an in-memory attached reference to Equipment e, but I want a detached reference to it, so that I can compare old database values to the in-memory set to see what has changed…

Answer 1

What you are creating here is not a detached query* – it’s an Equipment instance. By adding the get() you are executing the query and producing an attached Equipment instance. To create the detached query take away the get():

def dQuery = new DetachedCriteria(Equipment).build {
    eq('name', ef.name)
}

and then later when you need to execute:

def e = dQuery.get()

If you want to detach the Equipment instance then you could call

e.discard()

• actually you are creating the detached query – it is just never assigned to anything so it’s sort of in the background.