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,…
Access InStr() function to SQL Server equivalent
What is the SQL Server equivalent to Access InStr() function? TargetField: String expression being searched SearchValue: String expression being sought StartPosition: Starting position for each search (optional) Access SQL InStr(TargetField, SearchValue) InStr(StartPosition, TargetField, SearchValue) SQL Server CHARINDEX(SearchValue, TargetField) CHARINDEX(SearchValue, TargetField, StartPosition)
Self-documenting code
Strong preference should be given to writing code that is self-documenting. A common approach is to write a lot of comments, but the problem with comments are twofold: It actually can harm the readability because it adds to the overall length of code to read and understand. It must be correct or it can end…
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…
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
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…
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…
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…
Using Microsoft Access Data in a Mail Merge
Suppose you have an Access Database containing the names and addresses of your customers. Every now and again you may want or need to send a standard letter to each customer who has opted in to such mailings. However, you are aware that these letters are going to look so much better, and work so…