Symptoms Whenever you run a SQL statement you get a “Too Few Parameters, expected X.” Cause Most common cause is misspelling or missing fields in the SQL statement. Resolution Check the SQL statement. If necessary, copy and paste to an Access query and test in the query to get it to highlight which part of…
How to Display a Form Automatically when your Application Opens
This is a quick tip on how to automatically display a form when the user opens your Access Application. In addition to improving User Friendliness, your database design will also appear much more professional. The step by step instructions below will display the Switchboard form in figure 1 immediately upon the application opening. This will…
Module level variables
It is common to create a big wall of declaration in a module such as this:
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Private strCompanyName As String Private dteOrderDate As Date Private lngOrderID As Long Private objEmail As Object Private objOutlook As Object |
While the code will compile and work fine, the discoverability and naming of the module level variables does become difficult and unwieldy. To help cut down on this ambiguity, it is recommended to create a private user-defined type…
Access DateValue() function to SQL Server equivalent
What is the SQL Server equivalent to Access DateValue() function? Access SQL DateValue([Event Timestamp]) SQL Server Equivalent cast([Event Timestamp] as date) convert(date, [Event Timestamp])
“Truthy” and “Falsy” Values
VBA is quite very loose in what it deems “truthy” and “falsy”. For example, this procedure can produce surprising result:
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If Me.MyBitField.Value = True Then 'It is true Else 'It is false End If |
At the first glance, it seems expected that if the bit field is set to 1, it would succeed. But in fact, it wouldn’t because True is equivalent to -1, not 1. Unless we…
Use TryGet pattern for transient values
A number of objects may have extra properties or something where it might not exist for all instances. A good example might be finding Controlsource property on an Access.Control variable:
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For Each ctl In Me.Controls Debug.Print ctl.ControlSource 'A potential error Next |
Not all controls have a ControlSource property and thus can fail to run. A common approach is to use OERN:
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For Each ctl In Me.Controls On Error Resume Next Debug.Print ctl.ControlSource 'A potential error On Error GoTo 0 Next |
This will work…
Using Microsoft Access Data in a Mail Merge
Suppose you have an Access Database containing the names and addresses of your customers. Every now and again you may want or need to send a standard letter to each customer who has opted in to such mailings. However, you are aware that these letters are going to look so much better, and work so…
Self-documenting code
Strong preference should be given to writing code that is self-documenting. A common approach is to write a lot of comments, but the problem with comments are twofold: It actually can harm the readability because it adds to the overall length of code to read and understand. It must be correct or it can end…
Enable and Disable a Form Control using VBA
I was working on a design for an Order Management Database, and one of the tasks I dealt with involved dynamically Enabling or Disabling one of the form’s Command Buttons’ using VBA. This gave me the idea for the present Access tip. The command button was located on a Customer Details form which had an Orders…
Use properties instead of constant or magic numbers
A common programming mistake is to hard-code literals that corresponds to some property. That is particularly true with certain controls like tab controls & pages. The tab control exposes a Value property that indicates the current tab and the pages contains a PageIndex property that indicates its position in the tabs of the control. Thus,…