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…
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…
Symptoms Whenever you run a SQL statement you get a “Too Few Parameters, expected X.” Cause Most common cause is misspelling or missing fields in the SQL statement. Resolution Check the SQL statement. If necessary, copy and paste to an Access query and test in the query to get it to highlight which part of…
What is the SQL Server equivalent to Access IIf() function? Access SQL IIf([ResultValue]>=1, [Result Value], Null) SQL Server CASE WHEN [Result Value]>=1 THEN [Result Value] ELSE NULL END
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])
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…
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: Forms(“SomeForm”).Visible = False This is legal code and will compile but we can’t be assured that…
VBA is quite very loose in what it deems “truthy” and “falsy”. For example, this procedure can produce surprising result: 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…
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…
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…