How to convert my TSQL query to LINQ - linq

Question

I am new to linq. I can't convert this SQL code to linq. Please help me. Thanks.
DECLARE #myHID BIGINT;
SET #myHID = 1;
WITH tblChild AS
(
SELECT *
FROM wbs.WBS w
WHERE w.ParentId = #myHID
UNION ALL
SELECT w2.*
FROM wbs.WBS w2
JOIN tblChild ON w2.ParentId = tblChild.hID
)
SELECT
tblChild.hID ,
Unit.ID, w3.wbsName + ' * ' + tblChild.wbsName as
structure ,
tblChild.FK_WbsBaseStructure_hID ,
tblChild.parentID ,
unitNumber ,
unitTitle ,
FK_UsageItem_ID,
usageTitle ,
nominalArea
FROM
tblChild
INNER JOIN
unit.Unit ON tblChild.hID = Unit.FK_WBS_hID
INNER JOIN
unit.UsageItem ON Unit.FK_UsageItem_ID = UsageItem.ID
LEFT JOIN
wbs.WBS w3 ON tblChild.parentID = w3.hID
Please convert this to linq code.
Thanks.

Answer 1

For translating SQL to LINQ query comprehension:
Translate FROM subselects as separately declared variables.
Translate each clause in LINQ clause order, leaving monadic operators (DISTINCT, TOP, etc) as functions applied to the whole LINQ query.
Use table aliases as range variables. Use column aliases as anonymous type field names.
Use anonymous types (new { }) for multiple columns
Left Join is simulated by using a into join_variable and doing another from from the join variable followed by .DefaultIfEmpty().
Replace COALESCE with the conditional operator and a null test.
SELECT * must be replaced with select range_variable or for joins, an anonymous object containing all the range variables.
SELECT fields must be replaced with select new { ... } creating an anonymous object with all the desired fields or expressions.
Proper FULL OUTER JOIN must be handled with an extension method.