nhibernate - Counting in hibernate using Criteria without unnecessary inner joins -

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i using criteria counting number of rows. consider class

class groupmembership{  public group  group{get;set;}  public member member{get;set;}  }

i have criteria fetches distinct members each group as:

detachedcriteria.for<groupmembership>("this") .createcriteria("group", "grp") .createalias("this.communitymember", "communitymember") .setprojection(projections.projectionlist() .add(projections.groupproperty("this.group.id"),"groupid")  .add(projections.countdistinct("this.communitymember.id"), "totalmembers"))

is there way can count without performing inner join communitymember.

update: adding sqls generated query

select   this_.groupid                                  y0_,          count(distinct communitym2_.communitymemberid) y1_     [groupmembership] this_          inner join [communitymember] communitym2_            on this_.communitymemberid = communitym2_.communitymemberid          inner join [group] grp1_            on this_.groupid = grp1_.groupid group this_.groupid

as can see can avoid inner join in sql. question whether same can done in criteria.

how about...

detachedcriteria.for<groupmembership>()                 .setprojection(projections.projectionlist()                     .add(projections.groupproperty("group"))                     .add(projections.countdistinct("communitymember")))

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