Entity Framework 4.0 new support for T-SQL

EF4.0 new Executestorequery,executestorecommand,executefunction and other methods, the perfect support for T-SQL

The following code is an example of a nightmare of left join queries and report data queries in the EF before using LINQ:

LINQ left-Join query N-representation example code

1 public list<info> getmapunitlist (int MapId)


2 {


3 var var1 = from Mu in EPM. Mapunit


4 Join us in EPM. Unitstatus


5 on MU. Unit equals us. Unit into _unitstatus


6 Join CU in EPM. Contractunit


7 on MU. Unit equals CU. Unit into _contractunit


8 where MU. Map.mapid = = MapId


9 Select New Info ()


10 {


map = mu. Map


12,


mapstatus = null


14,


mapunit = mu


16,


Unit = mu. Unit


18,


status = _unitstatus.select (a => a.status). FirstOrDefault ()


20,


contract = _contractunit.select (a => a.contract). FirstOrDefault ()


22,


customer = null


24,


Boothtype = null


26};


var var2 = from v1 in var1


join MS in EPM. Mapstatus


on new {map = V1.map, status = V1.status}


equals new {map = Ms. Map, status = Ms. Status} into _mapstatus


Select New Info ()


32 {


map = null


34,


Mapstatus = _mapstatus.firstordefault ()


36,


Notoginseng mapunit = V1.mapunit


38,


= V1.unit


40,


status = V1.status


42,


contract = V1.contract


44,


customer = null


46,


Boothtype = null


48};


var var3 = from v2 in var2


from Ubtl in EPM. Unitboothtype


where UBTL. Unit.unitid = = V2.unit.UnitId


join CC in EPM. Customercontract


on V2.contract equals CC. Contract into _customercontract


Select New Info ()


55 {


map = null


57,


mapstatus = V2.mapstatus


59,


mapunit = V2.mapunit


61,


unit = V2.unit


63,


status = V2.status


65,


contract = V2.contract


67,


customer = _customercontract.select (a => a.customer). FirstOrDefault ()


69,


Boothtype = Ubtl. Boothtype


71};


list<info> infos = var3. ToList ();


return infos;


74}