ACC2000: Using Eval Function with Parameters in Parameter Queries
ID: Q198462
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The information in this article applies to:
SUMMARY
Moderate: Requires basic macro, coding, and interoperability skills.
If you use the Eval() function with a parameter expression in the criteria
of a query, you do not need to explicitly declare the parameter in order
to run the query in code.
If you do not use the Eval() function and you do not explicitly declare the
parameter, you may receive the following error message when you run the
query in code, where n represents the number of parameters:
Run-time error 3061:
Too few parameters. Expected n.
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MORE INFORMATION
The following example demonstrates how to use the Eval() function with a
parameter expression in a query:
- Open the sample database Northwind.mdb.
- Create the following new query based on the Orders table:
Query: QryEval
----------------------------------------
Type: Select Query
Field: OrderID
Table: Orders
Field: OrderDate
Table: Orders
Criteria: =Eval("Forms!FrmEval!Text0")
- Save the QryEval query and close it.
- Create the following new form not based on any table or query in Design
view:
Form: FrmEval
-----------------------------
Caption: Eval Form
Text box:
Name: Text0
Command button:
Name: Command0
Caption: Run Query
OnClick: [Event Procedure]
- Set the OnClick property of the command button to the following event
procedure.
Private Sub Command0_Click()
Dim MyDB As Database
Dim MySet As RecordSet
Set MyDB = CurrentDb()
Set MySet = MyDB.OpenRecordSet("QryEval")
MySet.MoveFirst
MsgBox MySet!OrderID
MySet.Close
End Sub
- Save the FrmEval form, and then open it in Form view.
- Type 8/4/94 in the text box, and then click the Run Query button. Note
that a message box appears that displays an Order ID number.
If you want to further test what happens when you do not use the Eval()
function and you do not explicitly declare the query parameter, follow
these steps:
- Open the QryEval query in Design view.
- Change the OrderDate criteria to [Forms]![FrmEval]![Text0].
- Save the query and close it.
- Open the FrmEval form in Form view.
- Type 8/4/94 in the text box, and then click the Run Query button.
Note that you receive the following error message:
Run-time error 3061:
Too few parameters. Expected 1.
REFERENCES
For more information about parameter queries, click Microsoft Access Help
on the Help menu, type "parameter queries" in the Office Assistant or the
Answer Wizard, and then click Search to view the topics returned.
Additional query words:
Keywords : kbdta QryParm
Version : WINDOWS:2000
Platform : WINDOWS
Issue type : kbhowto