converting sql to linq (joins and group by) - linq

Question

I am converting an old webforms app to asp.net mvc and I am having issues converting one of my sql statements into linq. In particular, i need help with grouping and joins. I have tried several ways by looking at various examples here and none have worked for me.
SELECT cp.PartNumber, cp.PartDescription, PFEP.PFEPTx, PFEP.KBQty,
TX_QOH.QOH, TX_ReworkQOH.Rework_QOH as Rework, SUM(ShippingInput.Qty) AS
'Ocean'
FROM CustomerParts as cp
LEFT JOIN TX_QOH
ON cp.PartNumber = TX_QOH.PN
LEFT JOIN TX_ReworkQOH
ON cp.PartNumber = TX_ReworkQOH.PN
LEFT JOIN ShippingInput
ON cp.PartNumber = ShippingInput.PN AND ShippingInput.Status <> 'Received'
LEFT JOIN PFEP
ON cp.PartNumber= PFEP.PN
WHERE cp.PartType = 'Actuator Part' AND cp.Division = 'Bayne' AND cp.Active
= 'Yes' AND TX_QOH.QOH = '0'
Group By cp.PartNumber, TX_QOH.QOH, TX_ReworkQOH.Rework_QOH,
cp.PartDescription, PFEP.PFEPTx, PFEP.KBQty
Order By cp.PartNumber ASC

Answer 1

This is obviously untested, and there may be null issues with trying to access fields when they may not exist due to the left join (e.g. SUM(ShippingInput.Qty)), which is why I moved some of the tests to lambda Where on the join
from cp in CustomerParts
join r_tx_qoh in TX_QOH.Where(r => r.QOH == "0") on cp.PartNumber equals r_tx_qoh.PN into j_tx_qoh
from r_tx_qoh in j_tx_qoh.DefaultIfEmpty()
join r_tx_reworkqoh in TX_ReworkQOH on cp.PartNumber equals r_tx_reworkqoh.PN into j_tx_reworkqoh
from r_tx_reworkqoh in j_tx_reworkqoh.DefaultIfEmpty()
join r_shippinginput in ShippingInput.Where(r => r.Status != "Received") on cp.PartNumber equals r_shippinginput.PN into j_shippinginput
from r_shippinginput in j_shippinginput.DefaultIfEmpty()
join r_pfep in PFEP on cp.PartNumber equals r_pfep.PN into j_pfep
from r_pfep in j_pfep.DefaultIfEmpty()
where cp.PartType == "Actuator Part" && cp.Division == "Bayne" && cp.Active == "Yes"
group new { cp, r_pfep, r_tx_qoh, r_tx_reworkqoh, r_shippinginput } by new { cp.PartNumber, r_tx_qoh.QOH, r_tx_reworkqoh.Rework_QOH, cp.PartDescription, r_pfep.PFEPTx, r_pfep.KBQty } into gcp
orderby gcp.Key.PartNumber
select new { gcp.Key.PartNumber, gcp.Key.PartDescription, gcp.Key.PFEPTx, gcp.Key.KBQty, tcp.Key.QOH, Rework = gcp.Key.Rework_QOH, Ocean = gcp.Sum(r => r.r_shippinginput.Qty) }

Answer 2

LINQ Version
var queryNew = (from cp in db.MasterPartLists
join tx in db.TxQohs on cp.CustomerPn equals tx.Pn into jTxQoh
from tx in jTxQoh.DefaultIfEmpty()
join c in db.ShipIns.Where(r => r.ShipInStatusId != 3) on cp.CustomerPn equals c.Pn into jShipIns
from c in jShipIns.DefaultIfEmpty()
join d in db.Pfeps on cp.CustomerPn equals d.CustomerPn into jPfeps
from d in jPfeps.DefaultIfEmpty()
where d.PartTypeId == parttype && cp.CustomerDivisionId == division && cp.ActivePartId == 1 && tx.Qoh == 0
group new {cp, d, tx, c} by new {cp.CustomerPn, tx.Qoh, cp.PartDescription, d.PfepTx, d.KbQty}
into gcp
orderby gcp.Key.CustomerPn
select new
{
gcp.Key.CustomerPn,
gcp.Key.PartDescription,
gcp.Key.PfepTx,
gcp.Key.KbQty,
gcp.Key.Qoh,
Ocean = (int?)gcp.Sum(r => r.c.Qty)
});
SQL Version
var queryNew = "SELECT cp.CustomerPn, cp.PartDescription, Pfeps.PFEPTx, Pfeps.KBQty, TxQohs.Qoh, SUM(ShipIns.Qty) AS 'Ocean' "
+ "FROM MasterPartLists as cp "
+ "LEFT JOIN TxQohs "
+ "ON cp.CustomerPn = TxQohs.Pn AND TxQohs.Qoh = '0' "
+ "LEFT JOIN ShipIns "
+ "ON cp.CustomerPn = ShipIns.Pn AND ShipIns.ShipStatusId <> '3' "
+ "LEFT JOIN Pfep "
+ "ON cp.CustomerPn = Pfeps.CustomerPn "
+ "WHERE cp.PartTypeId = parttype AND cp.CustomerDivisionId = division AND cp.ActivePartId = '1' "
+ "Group By cp.CustomerPn, TxQohs.Qoh, cp.PartDescription, Pfeps.PfepTx, Pfeps.KbQty "
+ "Order By cp.CustomerPn ASC ";