找到不同表的两列之和，然后减去它们的总和

Question

hi I want to make a query that first find the sum of two columns of different table then subtract it Example it is a visual basic program

Dim large_tbl As String
Dim sell_large As String

large_tbl = "SELECT Sum(No_Of_Bottle) FROM add_cotton where Cateogry='Large'"
sell_large = "SELECT Sum(Quantity) FROM Sell_Detail where Cateogry='Large'"

Adodc2.RecordSource = large_tbl - sell_large

Please help it shows an error type miss match

Answer 1

The two variables large_tbl and sell_large are strings -- just text as far as VB is concerned. You need to connect to a data source (ie a Sql Server) and execute a query to get a numerical result.

What you've asked the computer to do is subtract "blah" from "blah" and execute it.

What I guess you meant is something more like:

Dim oCNX as ADODB.Connection

:----Put code in here to open the connection to your database

Dim resultA as ADODB.Recordset
Dim resultB as ADODB.Recordset

Dim large_tbl As String
Dim sell_large As String

large_tbl = "SELECT Sum(No_Of_Bottle) FROM add_cotton where Cateogry='Large'"
sell_large = "SELECT Sum(Quantity) FROM Sell_Detail where Cateogry='Large'"

Set resultA = oCNX.Execute(large_tbl)
Set resultB = oCNX.Execute(sell_large)

Do while not oRS.Eof()

   Debug.Print "Result =" & (resultA(1).Value - resultB(1).Value)

   oRS.MoveNext
Loop

Or something like that.