datetime => how to have complete date with 00:00:00.000 – SQLServerCentral Forums
Does SQL Server always treat date strings as UTC by default?
How to change date format of Datetime data type?
[Question] How can I set the default date format for a table or a server/database?
You should try getting used to using yyyy-mm-dd (or / or maybe . delimiter) when manipulating dates in SQL, there's no ambiguity with this format. I believe SQL stores dates as an integer value. Displaying the date in a particular format is up to you really (see SET DATEFORMAT or FORMAT() function).
Date Data Type: https://docs.microsoft.com/en-us/sql/t-sql/data-types/date-transact-sql?view=sql-server-ver15
FORMAT: https://docs.microsoft.com/en-us/sql/t-sql/functions/format-transact-sql?view=sql-server-ver15
Edit: I believe Euroranger is right about the default displayed format being tied to the windows installation. And I thought there was a setting in SSMS for connections but can't find it, maybe it's an add-on that can set it.
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