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A Query won't give me the Integer value

Dave Elwood
Ranch Hand

Joined: Dec 27, 2002
Posts: 84
I'm writing a JavaEE6 app using NetBeans and persisting the entities on Glassfish
I've got a table of rooms with the Entity Room class to access the data.
The primary key is room_id and I need to find the last value used in order to bump up
the value and then insert a new room record.

So...in order to find the last value used I have a named query which calls the aggregate function MAX

In the session bean I fetch the value this way

Is there a member function of the Query object which returns the value MAX(r.roomId) ??
Something like :

this is what the whole Entity class looks like
Jayesh A Lalwani
Bartender

Joined: Jan 17, 2008
Posts: 2273
    
  28

When you say, "doesn't work", what error do you get? Is it a compilation error? Is it a runtime error?
Dave Elwood
Ranch Hand

Joined: Dec 27, 2002
Posts: 84
It compiles and runs, but there are three records, and the last record has room_id = 3 but this returns a value of 0
when I use

then I get a value of 2147483647

How do I get it to show me the value of 3??
Sameer Mali
Greenhorn

Joined: Dec 22, 2012
Posts: 2

try using
Dave Elwood
Ranch Hand

Joined: Dec 27, 2002
Posts: 84
Thank you Sameer, now it works like a charm.
 
It is sorta covered in the JavaRanch Style Guide.
 
subject: A Query won't give me the Integer value
 
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