Why does Excel have a problem when using code in Access?

When you use code to refer to Excel (and other programs as well) you need to be careful not to use any code that does not refer back to the instantiated application object. If you do so then you will find that Access instantiates another Excel (or other program) object which is not visible to…

new table

Creating a Make Table Query

Before we create the Make Table Query, you might like to create a new blank database file. This is so we have a separate database into which we can paste the new table from the query. In this exercise I have called it HistoricData.accdb. Here is the procedure to create a Make Table Query: Open…

Using Custom Functions in Calculated Controls

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…

Truthy and Falsy Values

“Truthy” and “Falsy” Values

VBA is quite very loose in what it deems “truthy” and “falsy”. For example, this procedure can produce surprising result: 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…

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

Access Web Apps

Access Web Apps to be retired

It was announced that Access Services is going to be retired. Details of the announcement may be found here: Updating the Access Services in SharePoint Roadmap. Additional timeline information along with possible methods for exporting your data out of an Access web app may be found here: Access web apps no longer supported. While these articles…

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,…

Prefer compile time errors over run time errors

In VBA, there are several features that allow us to do things that may not be checked at the compile time. In particular, it is possible to write several late-bound expressions which means that it can potentially contain run-time errors. One common misconception about late-binding is that it’s a matter of adding a reference and…

Designing a lookup table with logic

It is very common for us to embed some kind of logic based on a lookup table or in some cases, a column of a table. Because we have application logic connected to it, the code are fragile and subject to changes as the requirements develops. We want to avoid this situation where we might…

switchboard

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…