How to return only the Date from a SQL Server DateTime datatype?

Often in SQL Server, you might only need the date portion of a DateTime column without the accompanying time. Below are several approaches you can use to achieve this goal—ranging from simple casting and converting to leveraging more modern data types introduced in recent versions of SQL Server.

1. Use the CAST() or CONVERT() Function

1.1 CONVERT() with a Date Style

SQL Server’s CONVERT() function lets you specify a style (format) for the date/time output. To strip the time portion, you can use:

SELECT CONVERT(VARCHAR(10), GETDATE(), 23) AS OnlyDate;

• 23 corresponds to the YYYY-MM-DD format.
• You’ll get a VARCHAR(10) string, e.g., 2024-09-15, without the time part.

Commonly used date styles for returning just the date:

• 101 = MM/DD/YYYY
• 102 = YYYY.MM.DD
• 103 = DD/MM/YYYY
• 23 = YYYY-MM-DD (ISO format)

1.2 CAST() to DATE

Starting with SQL Server 2008, there is a dedicated DATE data type. You can simply cast a DateTime to DATE:

SELECT CAST(GETDATE() AS DATE) AS OnlyDate;

• This returns a date type without the time component.
• Great for direct usage in queries, but be mindful of indexing implications if used in WHERE clauses.

2. Best Approach for Modern SQL Server Versions

The recommended way—if your SQL Server version is 2008 or newer—is to store or convert to the DATE type when you don’t need time. It’s cleaner, less error-prone, and avoids confusion about hidden time portions or midnight defaults.

3. Performance Considerations

3.1 Using Functions in WHERE Clauses

If you apply CAST() or CONVERT() on a column inside the WHERE clause, the database might not be able to use an existing index on that column. For large tables, consider rewriting your queries to avoid function calls on indexed columns, or store a separate DATE column if that suits your data model.

3.2 Always Check Data Requirements

Truncating time may cause you to lose valuable information if your data actually needs it. Align this practice with your project’s data requirements and avoid one-size-fits-all solutions.

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Conclusion

Returning only the date portion from a DateTime value in SQL Server can be as simple as using CAST(... AS DATE) or CONVERT(...) with the appropriate style. For modern SQL Server environments (2008 and above), casting to the DATE type is the most straightforward and recommended approach. Keep an eye on performance implications, particularly if you’re using these functions in WHERE clauses.

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