Hardware matters. Invest in a faster PC and your Microsoft Access databases will run faster. Be alert for sellers packaging fast processors with minimal memory and a slow hard drive to keep prices low. Look at all aspects of the purchase when database speed is a priority. A faster hard drive is worth the investment…
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:
|
1 2 3 4 |
SELECT c.CompanyID, c.CompanyName FROM Companies; |
And only display CompanyName in a textbox but not show the CompanyID….
#LateBind Constant
In standard code, we make use of #LateBind conditional compilation constant, which is typically defined via project’s Conditional Compilation Argument in the dialog: NOTE: The dialog can be found via Tools → <project name> Properties, which is located below the Options menu item. The menu item caption will be different as it includes the project…
“Truthy” and “Falsy” Values
VBA is quite very loose in what it deems “truthy” and “falsy”. For example, this procedure can produce surprising result:
|
1 2 3 4 5 |
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…
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:
|
1 |
Forms("SomeForm").Visible = False |
This is legal code and will compile but we can’t be assured that this will…
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…
Microsoft Access 2003 Language Reference [Access 2003 VBA Language Reference]
This reference contains conceptual overviews, programming tasks, samples, and references to guide you in developing solutions based on Microsoft Access. The reference contains the following sections: What’s New: Provides a list of new members by object and in alphabetical order. Concepts: Provides important concepts for developing custom Access solutions. Reference: Provides reference materials for the Access…
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:
|
1 2 3 |
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:
|
1 2 3 4 5 |
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…
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,…
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…







