How do I resolve this query? - ms-access

Question

I receive runtime error 3122 :
You tried to execute a query that does not include the specified expression count(*)*t2.Daily_Charge_HKD as part of the aggregate function
What I want to do in the query:
I want to group all the record in Opt_In_Customer_Record by event_plan_code, and have a total count for each of the code, then I reference the daily_charge from the daily_charge table by t1.event_plan_code = t2.event_plan_code, and multiply the daily_charge with the total count for each of the code
Here is my code:
Private Sub btnGenDaily_Click()
Dim filename As String
Dim prefix As String
Dim qryDef As DAO.QueryDef
Dim dbs As DAO.Database
Set dbs = OpenDatabase(CurrentDb.Name)
If IsNull(txtInputPath.value) Then
MsgBox "Please enter a valid input file location."
Else
If FileExists(txtInputPath.value) Then
If IsNull(txtOutputPath3.value) Then
MsgBox "Please enter a valid output file location."
Else
prefix = GetFileNamePrefix(txtInputPath.value)
sql = "select t1.event_plan_code, count(*), count(*)*t2.Daily_Charge_HKD " & _
"from Opt_In_Customer_Record t1 Inner Join Daily_Charge t2 " & _
"On (t1.event_plan_code=t2.event_plan_code and t2.Home_BMO='" & prefix & "') " & _
"group by t1.event_plan_code " & _
"order by t1.event_plan_code "
MsgBox sql
If ObjectExists("Query", "getDailyCharge") Then
DoCmd.DeleteObject acQuery, "getDailyCharge"
End If
With dbs
.QueryTimeout = 0
Set QueryDef = .CreateQueryDef("getDailyCharge", sql)
End With
strPathToSave = txtOutputPath3.value
DoCmd.TransferSpreadsheet acExport, acSpreadsheetTypeExcel9, "getDailyCharge", strPathToSave, True
MsgBox "Daily charge report generated."
End If
Else
MsgBox "Input file does not exist. Please enter again."
End If
End If
End Sub

Answer 1

I know you mentioned in a comment that you don't want to group by "t2.Daily_Charge_HK", but to use that in the way you are doing with access you will need to group it, because of your join I'm guessing you only have one Daily Charge value for each event plan code so the grouping in this case won't be a problem. e.g. all event plan codes with id of 1 and Home BMO a prefix of x will have the same charge rate.
Change:
sql = "select t1.event_plan_code, count(*), count(*)*t2.Daily_Charge_HKD " & _
"from Opt_In_Customer_Record t1 Inner Join Daily_Charge t2 " & _
"On (t1.event_plan_code=t2.event_plan_code and t2.Home_BMO='" & prefix & "') " & _
"group by t1.event_plan_code " & _
"order by t1.event_plan_code "
Into:
sql = "select t1.event_plan_code, count(*), count(*)*t2.Daily_Charge_HKD " & _
"from Opt_In_Customer_Record t1 Inner Join Daily_Charge t2 " & _
"On (t1.event_plan_code=t2.event_plan_code and t2.Home_BMO='" & prefix & "') " & _
"group by t1.event_plan_code, t2.Daily_Charge_HKD " & _
"order by t1.event_plan_code, t2.Daily_Charge_HKD "
Hope this helps

Answer 2

Finally I come up with this solution and it works:
sql = "select t1.event_plan_code, Count, Count*Daily_Charge_HKD As 'Count * Daily_Charge_HKD' " & _
"from (select event_plan_code, count(*) As Count " & _
"from Opt_In_Customer_Record " & _
"group by event_plan_code " & _
"order by event_plan_code) t1, Daily_Charge t2 " & _
"where t1.event_plan_code=t2.event_plan_code and t2.Home_BMO='" & prefix & "' " & _
"order by t1.event_plan_code"