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…
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:
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SELECT c.CompanyID, c.CompanyName FROM Companies; |
And only display CompanyName in a textbox but not show the CompanyID….
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…
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 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)
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…
“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…
Creating a Make Table Query
Before we create the Make Table Query, you might like to create a new blank database file. This is so we have a separate database into which we can paste the new table from the query. In this exercise I have called it HistoricData.accdb. Here is the procedure to create a Make Table Query: Open…
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,…
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…




