SYSDATETIME (Transact-SQL)

Artikkeli
09/03/2024

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW)

Returns a datetime2(7) value that contains the date and time of the computer on which the instance of SQL Server is running.

Note

SYSDATETIME and SYSUTCDATETIME have more fractional seconds precision than GETDATE and GETUTCDATE. SYSDATETIMEOFFSET includes the system time zone offset. SYSDATETIME, SYSUTCDATETIME, and SYSDATETIMEOFFSET can be assigned to a variable of any of the date and time types.

Azure SQL Database (with the exception of Azure SQL Managed Instance) and Azure Synapse Analytics follow UTC. Use AT TIME ZONE in Azure SQL Database or Azure Synapse Analytics if you need to interpret date and time information in a non-UTC time zone.

For an overview of all Transact-SQL date and time data types and functions, see Date and Time Data Types and Functions (Transact-SQL).

Transact-SQL syntax conventions

Syntax

SYSDATETIME ( )

Return Type

datetime2(7)

Remarks

Transact-SQL statements can refer to SYSDATETIME anywhere they can refer to a datetime2(7) expression.

SYSDATETIME is a nondeterministic function. Views and expressions that reference this function in a column cannot be indexed.

Note

SQL Server obtains the date and time values by using the GetSystemTimeAsFileTime() Windows API. The accuracy depends on the computer hardware and version of Windows on which the instance of SQL Server is running. The precision of this API is fixed at 100 nanoseconds. The accuracy can be determined by using the GetSystemTimeAdjustment() Windows API.

Examples

The following examples use the six SQL Server system functions that return current date and time to return the date, time or both. The values are returned in series; therefore, their fractional seconds might be different.

A. Getting the current system date and time

SELECT SYSDATETIME()  
    ,SYSDATETIMEOFFSET()  
    ,SYSUTCDATETIME()  
    ,CURRENT_TIMESTAMP  
    ,GETDATE()  
    ,GETUTCDATE();  
/* Returned:  
SYSDATETIME()      2007-04-30 13:10:02.0474381  
SYSDATETIMEOFFSET()2007-04-30 13:10:02.0474381 -07:00  
SYSUTCDATETIME()   2007-04-30 20:10:02.0474381  
CURRENT_TIMESTAMP  2007-04-30 13:10:02.047  
GETDATE()          2007-04-30 13:10:02.047  
GETUTCDATE()       2007-04-30 20:10:02.047  
*/

B. Getting the current system date

SELECT CONVERT (date, SYSDATETIME())  
    ,CONVERT (date, SYSDATETIMEOFFSET())  
    ,CONVERT (date, SYSUTCDATETIME())  
    ,CONVERT (date, CURRENT_TIMESTAMP)  
    ,CONVERT (date, GETDATE())  
    ,CONVERT (date, GETUTCDATE());  
  
/* All returned 2007-04-30 */

C. Getting the current system time

SELECT CONVERT (time, SYSDATETIME())  
    ,CONVERT (time, SYSDATETIMEOFFSET())  
    ,CONVERT (time, SYSUTCDATETIME())  
    ,CONVERT (time, CURRENT_TIMESTAMP)  
    ,CONVERT (time, GETDATE())  
    ,CONVERT (time, GETUTCDATE());  
  
/* Returned  
SYSDATETIME()      13:18:45.3490361  
SYSDATETIMEOFFSET()13:18:45.3490361  
SYSUTCDATETIME()   20:18:45.3490361  
CURRENT_TIMESTAMP  13:18:45.3470000  
GETDATE()          13:18:45.3470000  
GETUTCDATE()       20:18:45.3470000  
*/

Examples: Azure Synapse Analytics and Analytics Platform System (PDW)

D: Getting the current system date and time

SELECT SYSDATETIME();

Here's the result set.

--------------------------  
7/20/2013 2:49:59 PM

Jaa