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c#linqrandom

linq: order by random

How can I change below code, to each time get 50 different random data from database?

return (from examQ in idb.Exam_Question_Int_Tbl
      where examQ.Exam_Tbl_ID==exam_id
      select examQ).OrderBy(x=>x.Exam_Tbl_ID).Take(50);
Solution

  • http://msdn.microsoft.com/en-us/library/system.guid.newguid.aspx

    return (from examQ in idb.Exam_Question_Int_Tbl
      where examQ.Exam_Tbl_ID==exam_id
      select examQ).OrderBy(x => Guid.NewGuid()).Take(50);

    If this is LINQ-to-SQL you could simply add a ORDER BY NEWID() to your SELECT statement.

    As commented it might be better to use an algorithm like Fisher-Yates Shuffle, here is an implementation: https://stackoverflow.com/a/375446/284240