ขอวิธีการเขียน หรือ ตัวอย่าง เกี่ยวกับการ Sum Column ของ ***Datagrid (VB.NET)

Imports System.Net
Imports System.Web.Http

Namespace Controllers
    Public Class extDashboardController : Inherits ApiController

        'สถานะใบสั่งซื้อ
        <HttpGet>
        <Route("api/extDashboard/GetPOStatus_dashBoard")>
        Public Function GetPOStatus_dashBoard() As IHttpActionResult
            Dim strSQL0 =
<Suparuck>
DECLARE @budgetYear VARCHAR(max);
SET @budgetYear = (
		SELECT TOP (1) BUDGET.year
		FROM BDG_TYPE
		INNER JOIN BUDGET ON BDG_TYPE.BDGCODE = BUDGET.type
		WHERE BUDGET.BudgetOpen = 'O'
		);
--SELECT @budgetYear;
IF @budgetYear IS NOT NULL
BEGIN
	SELECT TblPOStatus.StatusCode,
		TblPOStatus.StatusName,
		FORMAT(COUNT(MS_PO.PO_NO), 'N0') AS Items,		
		FORMAT(SUM(TOTAL_COST), 'N2') AS Total
	FROM MS_PO
	INNER JOIN TblPOStatus ON TblPOStatus.StatusCode = MS_PO.STATUS
	GROUP BY TblPOStatus.StatusCode,
		TblPOStatus.StatusName,
		LEFT(PO_NO, 2)
	HAVING LEFT(PO_NO, 2) = RIGHT(@budgetYear, 2)
	ORDER BY TblPOStatus.StatusCode;
END
--ELSE
--BEGIN
--	SELECT TblPOStatus.StatusCode,
--		TblPOStatus.StatusName,
--		COUNT(MS_PO.PO_NO) AS Items,
--		LEFT(PO_NO, 2) AS BudgetYear,
--		SUM(TOTAL_COST) AS Total
--	FROM MS_PO
--	INNER JOIN TblPOStatus ON TblPOStatus.StatusCode = MS_PO.STATUS
--	GROUP BY TblPOStatus.StatusCode,
--		TblPOStatus.StatusName,
--		LEFT(PO_NO, 2)
--	HAVING LEFT(PO_NO, 2) = RIGHT(@budgetYear, 2)
--	ORDER BY TblPOStatus.StatusCode;
--END                  
</Suparuck>

            Dim dt = Sexy_DatabaseVB.DbHelper.Query(strSQL0.Value)
            If dt.Rows.Count = 0 Then 'ไม่ได้เปิดงบประมาณ BUDGET.BudgetOpen
                'TODO
            End If
            Return Ok(dt.AsEnumerable().ToList())
        End Function

        ' มูลค่ายาและเวชภัณฑ์คงคลัง ณ คลังยาย่อย
        <HttpGet>
        <Route("api/extDashboard/SubStockValue_dashBoard")>
        Public Function GetSubStockValue_dashBoard() As IHttpActionResult
            Dim strSQL0 =
<Suparuck>
SELECT DEPT_ID.DEPT_NAME, FORMAT(SUM(TOTAL_VALUE), 'N2') AS TotalAmount
FROM SUBSTOCK INNER JOIN DEPT_ID
ON DEPT_ID.DEPT_ID = SUBSTOCK.DEPT_ID AND TOTAL_VALUE IS NOT NULL
GROUP BY DEPT_NAME ORDER BY SUM(TOTAL_VALUE) DESC           
</Suparuck>

            Dim dt = Sexy_DatabaseVB.DbHelper.Query(strSQL0.Value)
            'If dt.Rows.Count = 0 Then 'ไม่ได้เปิดงบประมาณ BUDGET.BudgetOpen
            '    'TODO
            'End If
            Return Ok(dt.AsEnumerable().ToList())
        End Function

    End Class
End Namespace