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…

Use controls, not fields

Sometimes we need to use fields from a RecordSource that aren’t shown on the form. It is legal to reference them directly even if they don’t have a control. For example, we can have a form bound to a RecordSource like so:

And only display CompanyName in a textbox but not show the CompanyID….

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…

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,…

drag and drop in Access

Drag & Drop and Conditional Sorting in Microsoft Access

Drag and Drop In MS Access Doug was on a roll in January of 2004 when he wrote his article on drag and drop in MS Access. He tested it now using Access 2016 and it still works. This article shows you how to add drag-and-drop to your Access application using combinations of multi-value and…

Access CDate() function to SQL Server equivalent

What is the SQL Server equivalent to Access CDate() function? Access SQL CDate([Event Timestamp]) SQL Server Equivalent cast([Event Timestamp] as datetime) convert(datetime, [Event Timestamp])

MODULE LEVEL VARIABLES

Module level variables

It is common to create a big wall of declaration in a module such as this:

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…

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:

This is legal code and will compile but we can’t be assured that this will…