CODEWITHSUNDEEP
linqdatatable
Web Development Hurricane
Web Development Hurricane

Reputation: 209

Inner join in Linq with more than 2 datatables

i have 3 tables

t1==>

 t1.ID    t1.co1     t1.col2

 1       a         b              
 2       a         b

t2==>

 t2.ID    t2.co1     t2.col2

  1       a         b              
  2       a         b

t3==>

 t3.ID    t3.co1     t3.col2

 1       a         b              
 2       a         b

i want inner join between all three tables using Linq and want selected column in 4th datatable.

equivalent sql query:

SELECT t1.ID,t2.col1,t3.col2 
  FROM t1
INNER JOIN t2 ON t1.ID=t2.ID
INNER JOIN t3 ON t1.ID=t3.ID

t4==>

 t1.ID    t2.co1     t3.col2

 1        a         b              
 2        a         b

Upvotes: 2

Views: 4462

Answers (2)

Kaf
Kaf

Reputation: 33809

Use LoadDataRow() to get a DataTable from an anonymous type as here. Else Result.CopyToDataTable().

//Get the column list as same as table1 to new datatable
DataTable table4 = table1.Clone();

var Result = 
  from x in t1.AsEnumerable() join 
       y in t2.AsEnumerable() on x.Field<int>("ID") equals y.Field<int>("ID") join 
       z in t3.AsEnumerable() on x.Field<int>("ID") equals z.Field<int>("ID")
  select new table4.LoadDataRow( 
       new object[] { 
              x.ID, 
              y.col1, 
              z.col2 
           }, false);

Upvotes: 1

Alex
Alex

Reputation: 8937

Something like this 

var Result = 
    from row1 in t1
    join row2 in t2 on row1.ID equals row2.ID
    join row3 in t3 on row1.ID equals row3.ID
    select new { ID = row1.ID, Col1 = row2.col1, Col2 = row3.col2 }

DataTable dt = Result.CopyToDataTable();

Upvotes: 3

Related Questions