DLookup won't return value from Combo Box

[AdmiralN]

Hi,

I have a problem that had me going around in circles for days now.

I have a combo box which updates from another combo box correctly. I'm now trying to get trying to get a text box to display a value based on the selection from the second combo box. My after event code is:

Private Sub cboActivity_AfterUpdate()
Me.cboRateHigh = DLookup("ProductivityRateHigh", "tblUnitPeriod", "ID= ' " & Me.cboActivity & " ' ")
End Sub

ID is the primary key and a number. The value returned in the combo box is text. I think this is where the issue is, because for some reason the Combo box doesn't seem show the PK (number) if I display the other columns.

I'm currently getting a run-time error 3464 'Data type mismatch in criteria expression'.

Thanks in advance for the help.

[NeoPa]

Put very simply, your quotes tell DLookup() that the value is a string and NOT a number (See Quotes (') and Double-Quotes (") - Where and When to use them).

[twinnyfo]

Not to mention that your quotes are including extra spaces on each side of your Combo Box's value, so, even if it could have been able to find that value taken as a string (which it might), you were looking for the wrong value in the first place.

As NeoPa suggests, your proper syntax should be:

Me.cboRateHigh = _
    DLookup("ProductivityRateHigh", _
            "tblUnitPeriod", _
            "ID=" & Me.cboActivity)

However, this assumes that the Combo Box's bound column is the Primary Key.

[NeoPa]

Thanks Twinny. That makes the concept clearer.

[AdmiralN]

Thanks very much for your help and also to NeoPa.

I have tried your correction and I'm now getting run-time error 3075
syntax error (missing operator) in query expression 'ID=(the variable)'.

I think the problem now is, as you suggested, the that the combo boxs Primary Key is not the bound column, as I can't see any values if I try to view all columns in the combo box.

The the after event code for the combo box is:

Private Sub cboPackageNumber_AfterUpdate()
Dim strSql As String
strSql = "SELECT o.Activity" & vbCrLf & _
"FROM tblActivity AS o" & vbCrLf & _
"WHERE o.PackageID = '" & cboPackageNumber.Value & "'" & vbCrLf & _
"ORDER BY o.PackageID;"
Debug.Print strSql
cboActivity.RowSource = strSql
End Sub

Thanks again in advance.

[twinnyfo]

Your SQL should be

SELECT o.PackageID, o.Activity .....

You also need to make sure the combo box is formatted for two columns, with the first column being bound.

Hope this hepps.

[AdmiralN]

Thanks so much for your help! That's what I couldn't figure out.