asp.net mvc - Excluding specific records using LINQ query - 


 studentid   session   semester   subject  1           2012      1          1 1           2012      1          2 1           2012      1          3 1           2012      1          4 1           2012      1          5 1           2012      2          6 1           2012      2          7 1           2012      2          8 1           2012      2          9 1           2012      2          10 1           2013      2          1 1           2013      2          13 1           2013      2          14 1           2013      2          15 1           2013      2          16 1           2013      3          17 1           2013      3          18 1           2013      3          19 1           2013      3          20 1           2013      3          21

i don't know can name query want generate. searched lot couldn't find result.
want write query me select records of semester 1,2 , 3 want exclude records same semester of different session. (i want retrieve semester 1 of 2012 , 2 , 3 of 2013).

action repeated unspecified session , semester.

i can't figure out query meant represent, can use linq achieve result.

where par down results , selectmany join multiple sequences.

var studentdata = ...; // table of data  var studentid = ...; // student id  var requestedrecords = new []      {         new { session = 2012, semester = 1 },         new { session = 2013, semester = 2 },         new { session = 2013, semester = 3 },     };  var query = requestedrecords.selectmany(                 rr => studentdata.where(                           ss => ss.studentid == studentid                              && ss.session == rr.session                               && ss.semester == rr.semester)             );

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