ON a.c1=b.c2 AND b.c3='n'. https://www.mssqltips.com › sqlservertip › 3169 › understanding-linq-to-join-multiple-tables-where-null-match-are-expected. Here data source means list. In this article, we will discuss how to join multiple data sources using LINQ. How to Join Two Tables by Multiple Columns in SQL Eg: select new { CTLJCRJOB, CTLRFDSTM } If you need it flattened, then you will have to write out the mapping yourself, but will still be very trivial. Group By Multiple Column In LINQ in C# - Entity Framework Query Expression This seems confusing at first but once you get acquainted with the way the SQL is composed from the expressions it will make a lot more sense, under the covers this will generate the type of join you are looking for. So we are using list collection to create three data sources with student details, … var query = from t1 in myTABLE1List // List