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…
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…
Normalize all constraints’ & indices’ names
Constraints that are created by SSMA or by user via SSMS tend to have ugly names. Worse, auto-generated names are not stable across backups. Meaning if you restore a new database based on a copy of another database, the constraint names will change. That create huge problems during migrations because scripts that references constraint will…
#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…
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…
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…
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…
“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…
IS NULL: Understanding and Using the Null Value in Microsoft Access
In Microsoft Access, a null value is a value that is not assigned or unknown. When working with databases, it’s important to understand how to use and identify null values in order to ensure accurate and efficient data management. The IS NULL operator is one of the most useful tools for working with null values…
Access 2003 Technical Articles
In this section of the MSDN Library, you’ll find technical articles that demonstrate how to build and deploy complex Access 2003 runtime-based solutions, automate Access from another application; use the new XML features in Access 2003, and even how you can animate Access 2003. You can use the TOC to your left to navigate through…