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…

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

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…

ID vs Code

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 2003

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…

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:

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…

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…

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….

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…