entity framework 4 - Linq to Entities: How to copy records from one table to another efficiently? -

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we have event system organizes data date , time. copy data old event new event starter, modify it.

this in linq:

  • get source objects locally .tolist()
  • for each item create new object
  • copy non-primary key values new object , set new primary key
  • add object table

this generates tremendous amount of database calls. it's wrapped in transaction @ least.

this statement in sql. way make linq efficient without embedding sql?

insert targettable (eventid, two, three, 4 five) select @neweventid eventid, two, three, four, 5   targettable   eventid = @eventid

no can't make ef code more efficient. how ef works. if want efficiency wrap sql stored procedure, map stored procedure in ef designer , call sp.

if can't create stored procedure execute sql directly. can use:

objectcontext.executestorecommand(...)

this method available in ef4.


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