![]() If you were not aware of that module, I strongly urge you to open the VBA Object Browser (Hit in the VBA-Editor) and take a look at the available functions.Ī word on Date arithmetic. There are quite a few built-in Date/Time-related functions in the VBA.DateTime-Module. I rather type in the conversion functions to make the intention of the code clearer. Nevertheless, I prefer to be explicit in my code. ![]() An implicit conversion between these types works all the same. The CDbl and CDate-Functions in that sample are actually not required. Additionally, a Date when being displayed as or converted to a string will use the General Date format for the text representation of the Date. By being a Date instead of just a Double the numeric value gets its true meaning. The specific Date data type does not add much to its Double core. The internal value, however, is exactly the same. The MessageBox will display different text representations of the variables depending on their type. It is immediately converted to a double and afterward back to date. The above sample uses the Now-Function to retrieve the current date and time. Public Sub TestDateConversion () Dim myDate As Date Dim myDouble As Double myDouble = CDbl ( Now ()) myDate = CDate ( myDouble ) MsgBox "The Double value " & myDouble & " represents the Date value " & myDate & "!" End Sub You will not use any information when you convert between these two types. Vice versa, you can use the CDate function to convert a Double to a Date. You can use the CDbl type conversion function to explicitly convert a Date to a Double type. Ī double value of 1.5 represents the Date/Time 12:00 PM. The decimal digits represent the fraction of a day thus the time of day. The integer part represents the days since December 30th, 1899. They are not exact! If you assign a value to a floating-point variable or database column the value that gets stored might be extremely close to the number you entered but not exactly that number.ĭateTime data is stored in the Double type in a simple but very effective way. However, there is one thing about floating point numbers you should be aware of. ![]() The details of the Double-precision floating-point data are beyond the scope of this article. A thing worth knowing is that the Date(/Time) data type is just a very thin wrapper around the data type Double.ĭouble is an 8-byte floating point data type and can store at least 15 significant digits. While we are at it, let’s take a closer look at how the VBA and Access Date/Time data type is set up internally. You need to be aware of this or you’ll be in for an unpleasant surprise sooner or later. In other words, it will show you the date only but it will still store the time as well. Setting the Format-Property of a table column will only affect how the data is displayed to you, it does not affect how data is actually stored in the database. “ Short Date”), to achieve a date-only column in your table.Ī Date/Time-column always stores date and time. The first important thing to internalize is, there is always date and time stored in this data type.Ī very common misconception is the idea that you can add a field to an Access table, choose the Date/Time data type, and then set the field’s Format-Property to any format that displays a date without time (e.g. There is a dedicated Date/Time data type in Access and a corresponding Date data type in VBA. I’ll try to provide comprehensive information and to give you some guidance on how to avoid common problems when working with dates in Access and VBA. I see beginners in Access development struggle with dates nearly every day in Access related forums. While dates in Access and VBA seem to be simple and straightforward at first sight, there are actually quite a few pitfalls connected to handling dates. So, what could go wrong when we work with dates in Access databases and VBA programming? We deal with them all the time in real life as well as in our digital lives. In general, we are very familiar with dates. ![]() By Philipp Stiefel, originally published:, last updated īased on a photo by Estée Janssens, used here under CC0 licensing ![]()
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