Integrating SQL and functions in Excel

Public Function MaxColumn(ParamArray lngArr() As Variant) As Long
    Dim i As Integer
    Dim max As Long
 
    max = lngArr(0)
    If UBound(lngArr()) > 0 Then
        For i = 1 To UBound(lngArr())
            If lngArr(i) > max Then max = lngArr(i)
        Next
    End If
    MaxColumn = max
End Function

Function SQL_ATR() As String
    Dim query1 As String, query2 As String, query3 As String, query4 As String
    Dim sSQL As String
    Dim iPeriod As Integer
    Dim dRefDate As Date
 
    dRefDate = #11/28/2008#
 
    query1 = "SELECT Ticker, Abs(Open-Close) AS OpCl, Abs(High-Low) AS HiLo, Open" & _
                " FROM 5401.txt" & _
                " WHERE dDate=" & CDateSQL(dRefDate) & _
                " GROUP BY Ticker, Open-Close, High-Low, Open"
 
    query2 = "SELECT TOP 1 Ticker AS YTicker, Close AS CloseYday" & _
                " FROM 5401.txt" & _
                " WHERE dDate<=" & CDateSQL(dRefDate) & _
                " GROUP BY dDate, Ticker, Close" & _
                " ORDER BY dDate DESC"
    query3 = "SELECT Ticker, OpCl, HiLo, Abs(Open-CloseYday) AS ClOp" & _
                " FROM (" & query1 & ") AS Q1 INNER JOIN (" & query2 & ") AS Q2" & _
                " ON Q1.Ticker = Q2.YTicker"
 
    sSQL = query3
 
    SQL_ATR = sSQL
End Function

x = application.max(workbooks("BookName").worksheets("SheetName").Range("A1:C5"))

debug.print x

Select max(value)
from (        select column1 as value from anywhere
        union select column2 as value from anywhere)