Linqer cannot convert: SQL syntax error: Each GROUP BY expression must contain at least one column reference

Question

I have this running query:

SELECT DISTINCT
       b.NAME AS [Service Name],
       CASE
           WHEN [a].[PAY_MODE_ID] IN ( 1, 2 ) THEN
               'OFFLINE'
           ELSE
               'ONLINE'
       END AS [Transaction Type],
       p.NAME AS [Payment Method],
       SUM(a.REQUESTED_QTY) AS [Transaction],
       SUM(a.ITEM_TOTAL) AS Income
FROM dbo.BILL_INFO_DETAIL AS a
    INNER JOIN dbo.SERVICE_INFO AS b
        ON a.SERVICE_CODE = b.SERVICE_CODE
    INNER JOIN dbo.PAY_MODE AS p
        ON a.PAY_MODE_ID = p.PAY_MODE_ID
WHERE (a.INPUT_STATUS = '1')
      AND (b.SERVICE_CODE IN ( 1610, 1611, 1612 ))
      AND (CONVERT(VARCHAR(2), a.STAMP_DATE, 101) IN ( '10', '11', '12' ))
      AND (CONVERT(VARCHAR(4), a.STAMP_DATE, 102) IN ( '2017' ))
      AND (b.FEE > 1)
GROUP BY b.NAME,
         CASE
             WHEN [a].[PAY_MODE_ID] IN ( 1, 2 ) THEN
                 'OFFLINE'
             ELSE
                 'ONLINE'
         END,
         p.NAME
ORDER BY [Transaction Type];

Linqer is not able to convert this to proper LINQ:

SQL syntax error: Each GROUP BY expression must contain at least one column reference.

This query is working in SQL Server. Any pointers?

Note:

• Removing the DISTINCT has no effect
• Removing the ORDER BY has no effect
• Removing the ; has no effect

Answer 1

Seems that all I had to do was to remove the CASE with PAY_MODE_ID. I modified the query apart from that change in order to make it production ready:

SELECT si.SERVICE_CODE,     
       si.NAME AS [ServiceName],
       bid.PAY_MODE_ID AS [PaymentId],
       p.NAME AS [PaymentName],
       SUM(bid.REQUESTED_QTY) AS [Transaction],
       SUM(bid.ITEM_TOTAL) AS [Income]
FROM BILL_INFO_DETAIL AS bid
    INNER JOIN dbo.SERVICE_INFO AS si
        ON bid.SERVICE_CODE = si.SERVICE_CODE
    INNER JOIN dbo.PAY_MODE AS p
        ON bid.PAY_MODE_ID = p.PAY_MODE_ID
WHERE (bid.INPUT_STATUS = '1')
      AND (si.SERVICE_CODE IN ( 1610, 1611, 1612 ))
      AND (CONVERT(VARCHAR(2), bid.STAMP_DATE, 101) IN ( '10', '11', '12' ))
      AND (CONVERT(VARCHAR(4), bid.STAMP_DATE, 102) IN ( '2017' ))
      AND (si.FEE > 1)
GROUP BY si.SERVICE_CODE,
         si.NAME,   
         bid.PAY_MODE_ID,
         p.NAME

This resulted in LINQ (slightly modified):

    from bid in db.BILL_INFO_DETAIL
    where
      bid.INPUT_STATUS == true &&
      (new int[] {1610, 1611, 1612 }).Contains(bid.SERVICE_INFO.SERVICE_CODE) &&
      (new int[] {10, 11, 12 }).Contains(bid.STAMP_DATE.Value.Month) &&
      bid.STAMP_DATE.Value.Year == 2017 &&
      bid.SERVICE_INFO.FEE > 1
    group new {bid.SERVICE_INFO, bid, bid.PAY_MODE} by new {
      bid.SERVICE_INFO.SERVICE_CODE,
      bid.SERVICE_INFO.NAME,
      bid.PAY_MODE_ID,
      Column1 = bid.PAY_MODE.NAME
    } into g
    select new {
      g.Key.SERVICE_CODE,
      ServiceName = g.Key.NAME,
      PaymentId = g.Key.PAY_MODE_ID,
      PaymentName = g.Key.NAME,
      Transaction = (int?)g.Sum(p => p.bid.REQUESTED_QTY),
      Income = (decimal?)g.Sum(p => p.bid.ITEM_TOTAL)
    }