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…
Designing a lookup table with logic
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…
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 File Extensions
Microsoft Access saves information under the following file formats: File Format Extension Access Project (2007, 2010) .adp Access Blank Project Template (2007, 2010) .adn Access Database (2007, 2010, 2013, 2016) .accdb Access Record-Locking Information (2007, 2010, 2013, 2016) laccdb Access Web App Reference .accdw Access Signed Packages .accdc Access Database, used for Add-ins .accda Access…
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…
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…
“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…
“Too Few Parameters” error fix
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…
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)




