JOIN and LEFT JOIN equivalent in LINQ with Method Syntax - sql

Question

I am converting a SQL query to LINQ that creates a left join with 1-to-1 mapping, and it has to be in Method Syntax. I have been pulling off my hair trying to accomplish this to no veil. I can do it in Lambda Syntax. Below is the example query I am trying to run. They are not actual code. Would someone point out what I am doing wrong?
SQL:
SELECT item.*, item_status.*
FROM item
LEFT JOIN item_status
ON item.ID = item_status.itemID
AND item_status.FLAGGED = true
WHERE item.published_date > "2008-06-19"
LINQ:
var linq_query = (
from selected_item in item
join selected_item_status in item_status
on selected_item.ID equals item_status.itemID into joined
from item_status in joined.DefaultIfEmpty()
where item_status.FLAGGED = true
select new {selected_item, selected_item_status}).ToList();

Answer 1

The join ... into becomes a GroupJoin and the second from becomes a SelectMany:
var linq_query = Item
.GroupJoin(
item_status.Where(x => x.selected_item_status.FLAGGED), // EDIT: Where clause moved here.
selected_item => selected_item.ID,
selected_item_status => selected_item_status.itemID,
(selected_item, joined) => new
{
selected_item,
statuses = joined.DefaultWithEmpty(),
})
.SelectMany(x => x.statuses.Select(selected_item_status => new
{
x.selected_item,
selected_item_status,
}))
// EDIT: Removed where clause.
.ToList();
It looks like the Where makes the left outer join unnecessary, as null statuses will be filtered out anyway.
EDIT: No, upon reviewing the SQL it looks like your LINQ query is slightly incorrect. It should be:
var linq_query = (
from selected_item in item
join selected_item_status
in (
from status in item_status
where status.FLAGGED
select status)
on selected_item.ID equals item_status.itemID into joined
from item_status in joined.DefaultIfEmpty()
select new {selected_item, selected_item_status}).ToList();