Custom functions work the same way as MS Access built-in functions such as DateAdd, DatePart and DSum, but are instead created ourselves as database developers. We do this by creating a public function with the VBA programming language and save it inside a global module within the database. Today I am going to explain how custom functions can be…
ID vs Code
There are cases where a table’s primary key is referred to often in the code. In fact, it might have some special meanings in code. It is highly encouraged to avoid the use of IDENTITY or AutoNumber (or any auto-incrementing schema) for those keys because it is also usually desirable to create a VBA Enum…
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,…
Pivoting a dynamic set
SQL Server does not allow for a dynamic set, which can be problematic if you need to pivot based on the data that comes from rows and you can have various values in the column. In general, you need a stored procedure and dynamic SQL in order to handle the dynamic pivots. This requires uses…
Access IIf() function to SQL Server equivalent
What is the SQL Server equivalent to Access IIf() function? Access SQL IIf([ResultValue]>=1, [Result Value], Null) SQL Server CASE WHEN [Result Value]>=1 THEN [Result Value] ELSE NULL END
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…
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…
Minimizing stateful code
First we need to define what a state is. A state means that the object has variable(s) that may cause it to behave differently, depending on the content of the variables. As an example, the Forms collection is stateful:
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Forms("SomeForm").Visible = False |
This is legal code and will compile but we can’t be assured that this will…
Access 2010: Unrecognized Database Format
I’ve been seeing more and more people having problems with the Unrecognized Database Format when creating or modifying an Access 2007 (accdb) format database in Access 2010 and then trying to open it again in Access 2007. The issue appears to be that Access 2010 does not have its own file format. When you add a…
Access UPDATE query to SQL Server
How do I convert an Access UPDATE query to SQL Server? Access SQL UPDATE Cars INNER JOIN UpdateList ON Cars.Parts = UpdateList.Parts SET Cars.Price = [Updatelist].[price] SQL Server UPDATE Cars SET Cars.Price = [Updatelist].[price] FROM Cars INNER JOIN UpdateList ON Cars.Parts = UpdateList.Parts




