In SQL, the DATETIME data type is used to represent date and time values. It is a composite data type that combines the DATE and TIME data types. The DATETIME data type is commonly used in database systems to store and manipulate time-related data, such as timestamps of when a particular event occurred.

The SQL DATETIME data type stores values with a precision of up to three decimal places, which represents fractions of a second. The syntax for defining a DATETIME column in SQL varies depending on the specific database system being used, but the most common syntax is:


The optional “fractional_seconds_precision” parameter specifies the number of digits to be used to represent fractions of a second. If this parameter is not specified, the default precision is three decimal places.

The DATETIME data type supports a wide range of date and time values, including values ranging from January 1, 1753, to December 31, 9999, with a precision of up to one microsecond. This means that you can store and manipulate date and time values with a high degree of accuracy and granularity.

Some common operations that can be performed on DATETIME data types include addition, subtraction, comparison, and formatting. For example, you can use the DATEADD function to add a specified number of days, months, or years to a DATETIME value. Similarly, you can use the DATEDIFF function to calculate the difference between two DATETIME values.

Overall, the SQL DATETIME data type is a powerful and flexible data type that allows you to store and manipulate time-related data with ease in SQL. It is an essential tool for developers and database administrators who need to work with temporal data in their applications and systems.