Nhibernate Linq In Clause
Is it possible to get Nhibernate linq to generate a query with an "In" clause? e.g. - Where AnID in (x,y,z)开发者_C百科
?
I don't know the state of nHibernate with respect to generating all the potential LINQ queries, but you should be able to use .Contains()
to generate an IN.
var list = new int[] { x, y, x };
var q = db.Entities.Where( e => list.Contains( e.AnID ) );
Agreed, this does work. I found the generated SQL for 'not in' to be strange though (as of 3.3.0 GA)
...
from
mytable t0_
where
case
when t0_.testValue in (
@p0 , @p1 , @p2
) then 1
else 0
end=@p3
@p0 = 9 [Type: Int32 (0)],
@p1 = 99 [Type: Int32 (0)],
@p2 = 109 [Type: Int32 (0)],
@p3 = False [Type: Boolean (0)],
...
Seems a bit odd to 'case' this when 'not in' would have been clearer (not that I plan on reading every line, but in a trace/profile maybe).
(... later that day ...)
I realized that the above 'strange' choice of SQL was only when I used
.Where(e => list.Contains(e.AnID) == false)
If I used
.Where(e => !list.Contains(e.AnID))
The SQL generated is much cleaner (using 'not in')
NHibernate has an option IsIn part of RestrictionExtensions
x => x.Name.IsIn( new[] {"a", "b"} )
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