How to write an Excel function which returns a value from an SQL database?

问题

I want to write the following function which should be used in an Excel worksheet:

=GetRecField("Foo Record Key", "FooField1")

...which will connect internally through ODBC to an SQL database, execute there an

SELECT FooField1 FROM MyTable WHERE KEY_FIELD='Foo Record Key';

and will return the resulting value as the result of the function GetRecField. The above SQL is granted to return only one record (IOW KEY_FIELD has an unique constraint).

Of course, the above function can be called multiple times in a worksheet so, please try to avoid a blind QueryTables.Add

TIA.

回答1:

You can write a custom function to do that

Open the VBA editor (ALT-F11)
Open Tools -> References, and make sure the "Microsoft ActiveX Data Objects 2.8 Library" and "Microsoft ActiveX Data Objects Recordset 2.8 Library" are selected
Right click VBAProject, and choose Insert -> Module
Open the module. Now you can create a custom function, like:

    Public Function GetItem(field As String, id As Integer) As String
        Set oConnection = New ADODB.Connection
        Dim oRecordset As ADOR.Recordset
        oConnection.Open "provider=sqloledb;data source=yourserver;" & _
            "Trusted_Connection=yes;initial catalog=yourdatabase;"
        Set oRecordset = oConnection.Execute( & _
            "select " & field & " from table where id = " & id)
        If oRecordset.EOF Then
            GetItem = "n/a"
        Else
            GetItem = oRecordset(field)
        End If
    End Function

You can now call the function from a cell:

=GetItem("fieldname";2)

The module is required because non-module functions can't be called from inside the spreadhseet.

回答2:

Why not use Excel's built-in database query functionality on a separate sheet (Data menu, Import External Data, New Database Query), then use VLOOKUP to extract values from that sheet?

回答3:

I solved a similar problem in Excel version 1808(?) by saving the database connection in one sheet and using a reference to the desired cell in other sheets.

Data > Get Data > From Database > From SQL Server Database
Enter the Server and Database names.
Open Advanced options and enter the query verbatim, then name it "connection_name".
Now that the query is available, open Data > Queries & Connections.
Right click on the connection and click Load To...
Select an unused location on an unused sheet and put it there.
In the target cell elsewhere in the file, enter =connection_name[[#All,][Column1]].

This certainly seems indirect in that I couldn't find a way to refer to the connection without it appearing in a sheet somewhere. But it worked for me and I wasn't able to find similar instructions elsewhere so I thought it could be informative.

来源：https://stackoverflow.com/questions/836065/how-to-write-an-excel-function-which-returns-a-value-from-an-sql-database

标签

sql

excel

odbc