asp.net - T-Sql to linq conversion issues (order by) -

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i'm having bit of issue converting following t-sql statement linq (using 4.0 entity framework)

i'm getting

unable cast type 'system.linq.iorderedqueryable1' type 'system.linq.iqueryable1'. linq entities supports casting entity data model primitive types.

t-sql

    select      i.id     , i.name inventory i.id in      (     select top 5 applicationid      lastviewed      group applicationid, someuserid     having someuserid = @someuserid     order max(id) desc     )

this have right (with linqer)

    dim query iqueryable(of inventory) =         d in ctx.inventories                     ((from e in ctx.lastvieweds _             group e _               e.applicationid, _               e.someuserid _              g = group _             dfaitedsid = user _             order g.max(function(p) p.id) descending _             select new { _               applicationid _             }).take(5)).contains(new {.applicationid = d.id}) _         select d

it crashes when line.

query.tolist()

thanks time.

your 'problem' in first line. query have specified returns iorderedqueryable(of inventory) trying assign variable of type iqueryable(of inventory). aren't getting error until query.tolist() deferred execution. can let compiler infer type if have 'option infer' set on in project , query like:

dim query =         d in ctx.inventories                     (from e in ctx.lastvieweds _             group e _               e.applicationid, _               e.someuserid _              g = group _             dfaitedsid = user _             order g.max(function(p) p.id) descending _             select applicationid take 5 _             ).contains(d.id) _         select d

or can change type of query iorderedqueryable(of inventory)

note: have works fine in linq sql, entities stricter when comes casting.

edit: alright, let's try dig little deeper this. tell me line blows following:

dim innerlist = (from e in ctx.lastvieweds _                 group e _                 e.applicationid, _                 e.someuserid _                 g = group _                 dfaitedsid = user _                 order g.max(function(p) p.id) descending _                 select applicationid take 5).tolist() dim query = (from d in ctx.inventories             innerlist.contains(d.id) _             select d).tolist()

don't forget pare results down bit if enumerating queries 'tolist()' much. types of both variables list(of inventory)


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