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 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
Access DateValue() function to SQL Server equivalent
What is the SQL Server equivalent to Access DateValue() function? Access SQL DateValue([Event Timestamp]) SQL Server Equivalent cast([Event Timestamp] as date) convert(date, [Event Timestamp])
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…
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:
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Forms("SomeForm").Visible = False |
This is legal code and will compile but we can’t be assured that this will…
Access NZ() function to SQL Server equivalent
What is the SQL Server equivalent to Access NZ() function? Access SQL NZ([Event Timestamp]) SQL Server Equivalent COALESCE([Event Timestamp],0) ISNULL([Event Timestamp],0) * do not confuse this with the Access isnull() function.
“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…
Module level variables
It is common to create a big wall of declaration in a module such as this:
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Private strCompanyName As String Private dteOrderDate As Date Private lngOrderID As Long Private objEmail As Object Private objOutlook As Object |
While the code will compile and work fine, the discoverability and naming of the module level variables does become difficult and unwieldy. To help cut down on this ambiguity, it is recommended to create a private user-defined type…
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…
Access CDate() function to SQL Server equivalent
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])