>>>

>>>   var query = from c in dtInstructors.AsEnumerable() 
>>>                                  where (from b in dtAllScheduled.AsEnumerable() where 1 == b.Field<Byte>("layer") 
>>>                                          && b.Field<   )

>>>
>>>based on http://www.telerik.com/forums/exists-query-in-dynamic-linq
>>
>>Add "select c" at the end to select your datarow from dtInstructors. Use CopyToDataTable (http://msdn.microsoft.com/en-us/library/system.data.datatableextensions.copytodatatable%28v=vs.110%29.aspx) to put the results back into a datatable if there are any results.
>
>For now I am struggling to write the query. I decided to try Any operator, but I can not figure out how to add second table.
>
>Here is what I have now and confused as what I wrote makes no sense and I don't know how to fix:
>
>

>  // Remove instructors who don't have anything planned
>                      var query = from c in dtInstructors.AsEnumerable().Any 
>                                   (from b in dtAllScheduled.AsEnumerable() where 1 == b.Field<Byte>("layer") 
>                                          && true==b.Field<Boolean>("schassign") && c.Field<String>("instr_id")== b.Field<String>("resource_id")
>                                          );

Try

var query = dtInstructors.AsEnumerable().Where(c => dtAllScheduled.AsEnumerable().Any(b => exists condition));