Select all columns after JOIN in LINQ
I have two tables, Table1
and Table2
. I want to perform, say, a left outer join:
var myOutput = from object1 in Table1
join object2 in Table2
on object1.Property1 equals object2.Property2 into Table3
from output in Table3.DefaultIfEmpty()
select new
{
object1.Property1,
object1.Property2,
//...
output.Property3,
output.Property4,
//...
};
As you can notice, I want to select all the properties of both objects from the resulting table (the enumerables considered while joining contain the objects of certain types - these are different for both relations). Of course, I can select the properties in the anonymous select, as shown in the example.
My question is how to avoid specifying all the properties manually? I would like to have something like SELECT * FROM TABLE3
, where TABLE3
is a resulting relation (after joining TABLE1
and TABLE2
).
Thanks in advance for the clues.
Solution 1:
You have to specify each manually if you want to project into a flattened type. Your other option is to just have your combined type contain both objects, and the objects will naturally bring along their properties.
select new
{
Object1 = object1,
Object2 = output
};
And you would work with it like myObj.Object1.Property1
, myObj.Object2.Property4
, etc.
One final option that still involves some manual work is to define an appropriate type and have a constructor or a builder method that does the work of segmenting out your object properties into a flattened type. You still perform the manual mapping, but you isolate it from your query logic.
select new CombinedType(object1, output);
//or
select builder.GetCombinedType(object1, output);