Please help me convert this sql to LINQ

Tag: linq

DECLARE @items table (
    pfid varchar(8),
    timestart datetime,
    timeend   datetime
)

insert INTO @items(pfid,timestart,timeend)
VALUES('123456','12:00 AM','3:00 AM')
,('987654', '2:00 AM', '4:00 PM')
,('492384', '3:00 PM', '9:00 PM')

SELECT * FROM @items a
    INNER JOIN @items b
        ON a.timestart < b.timeend
        AND b.timestart < a.timeend
        AND a.pfid != b.pfid

I need the select statement above converted to LINQ. In my code, I am working with a DataTable, named 'dt'. My table has three columns just like in the example above, exact same names and populated with this data.

I am struggling to create a LINQ query that will query my DataTable in the same fashion my SQL query is working with the temp table above. Please assist. Thanks in advance!

Best How To :

something in the line of...i didn't test this but you may have to do Datetime.Parse etc if needed...

(from r1 in dt.Rows.OfType<DataRow>()
 from r2 in dt.Rows.OfType<DataRow>()
 where r1["timestart"] < r2["timeend"] &&  r2["timestart"] < r1["timeend"] && r1["pfid"] != r2["pfid"]
 select new {R1=r1, R2=r2})

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something in the line of...i didn't test this but you may have to do Datetime.Parse etc if needed... (from r1 in dt.Rows.OfType<DataRow>() from r2 in dt.Rows.OfType<DataRow>() where r1["timestart"] < r2["timeend"] && r2["timestart"] < r1["timeend"] && r1["pfid"] != r2["pfid"] select new {R1=r1, R2=r2}) ...

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