If you input into that field a date, or a date and time, in a pattern that doesn’t match that in your Region Settings, then Access will exercise initiatives in interpreting your input. If you set the Data Type property of a field in an Access table to Date/Time, then Access will reject your attempt to input into that field anything that it fails to interpret as a date or as a date and time. Copy and paste any of the examples below into your Immediate Window and then press Enter to see the result. You can use the Immediate Window in Access’s Visual Basic Editor to test how Access works with dates. Add another decimal place - 0.666666 - to achieve 4:00:00 PM exactly.Ī number with digits to the left and right of the decimal point is how Access stores date and time together. 0.66666 represents 3:59:59 PM - very nearly two-thirds of the way through a day, at 15 hours, 59 minutes and 59 seconds. The decimal part of a number stored in a Date/Time field represents time as a fraction of 24 hours. Count 43843 and you’d be at January 13th 2020. Access stores January 1st 100 CE as the number -657434 December 31st 9999 CE, as 2958465.Ĭount one for each day since January 1st 100 CE to the date you have in mind and you have the number Access stores representing that date. The integer part of a number stored in a Date/Time field relates to Access's built-in calendar that runs from January 1st 100 CE to December 31st 9999 CE.
I believe I must make a database manage dates and times correctly irrespective of any tinkering a particular user may do to their Windows settings.Īccess stores input into a Date/Time field as a floating point number that is, a number with an integer part and a decimal part.
I illustrate them here because they have an influence on the results of some of the tests on Access’s conduct of dates and times that appear below.Īs a database developer, I never insist that a client adopts one set of Language Preferences over another. I don’t alter these default settings, for reasons I explain below. The settings shown above are for my computer, as supplied to me in the UK.
Then choose Region to display the Region dialog box. The setting is in Window 10’s Control Panel: open Control Panel and navigate via Clock and Region . Much of Access's response to dates and times, is determined by the region to which the computer you’re using is set. Will dates in reports produced by the database and sent to people outside the office be understood correctly by the recipients of those reports?.Do my queries work correctly if they include date filters or expressions based on dates?.Does the recorded date register as the same date with all users of the database?.Is Access’s record of the input date the same date as the user wants recorded?.In adopting a blueprint for dates, a database developer should have in mind questions like these: If you’re working in the United States and you’re guessing I’m a Brit writing this piece, you’d assume I meant. You and your computer are probably in agreement that refers to Tuesday 24 th September 2019. Expressions in Query Filters for Dates.Ĭonsider what you understand the date to be when you read.