SYSDATETIME

SYSDATETIME is a built‑in function in SQL Server that returns the current system date and time. It provides the server’s local date and time with high precision by returning a value of type datetime2(7), which includes up to 100 nanoseconds of fractional seconds. The function is non-deterministic because its result depends on the moment it is executed and the server’s clock.

Syntax and return type

- Syntax: SYSDATETIME()

- Return type: datetime2(7)

Behavior and usage

SYSDATETIME reflects the server’s local time and is commonly used for time stamping, logging, and other scenarios that require precise date-time values. Because it uses datetime2(7), it offers higher precision than many older date-time functions and avoids the fractional-second truncation seen with some alternatives. The function can be used in SELECT statements, INSERT statements, and within computed expressions, and it is suitable for defaults where a precise timestamp is desired.

Related functions

- GETDATE(): returns the current date and time as a datetime with lower precision.

- SYSUTCDATETIME(): returns the current date and time in UTC, as datetime2(7).

- SYSDATETIMEOFFSET(): returns the current date and time with time zone offset, as datetimeoffset(7).

- GETUTCDATE(): returns the current UTC date and time as datetime.

Notes

SYSDATETIME is introduced in SQL Server 2008 and is part of the family of functions used to obtain system time. Since it depends on the server clock, it should not be relied on for deterministic calculations or for cross-server time comparisons without normalizing to a common time basis.