DB2 10.5 for Linux, UNIX, and Windows

SET CURRENT TEMPORAL SYSTEM_TIME statement

The SET CURRENT TEMPORAL SYSTEM_TIME statement changes the value of the CURRENT TEMPORAL SYSTEM_TIME special register.

Invocation

This statement can be embedded in an application program or issued through the use of dynamic SQL statements. It is an executable statement that can be dynamically prepared.

Authorization

None required.

Syntax


                                     .-=-.                   
>>-SET CURRENT TEMPORAL SYSTEM_TIME--+---+--+-NULL-------+-----><
                                            '-expression-'

Description

NULL

Specifies the null value.

expression

Each expression can contain any of the following supported operands (SQLSTATE 428HY):

Constant
Special register
Variable (host variable, SQL variable, SQL parameter, transition variable, global variable)
Built-in scalar function whose arguments are supported operands. User-defined functions and non-deterministic functions are not supported in this context.
CAST specification where the cast operand is a supported operand
Expression using arithmetic operator and operands

Notes

Transaction considerations: The SET CURRENT TEMPORAL SYSTEM_TIME statement is not a committable operation. ROLLBACK has no effect on CURRENT TEMPORAL SYSTEM_TIME.
Effects on other special registers: The setting of the CURRENT TEMPORAL SYSTEM_TIME special register does not have any effect on the values of other special registers, specifically the CURRENT DATE and CURRENT TIMESTAMP special registers.

Examples

Example 1: Set the CURRENT TEMPORAL SYSTEM_TIME special register to the previous month.
```
   SET CURRENT TEMPORAL SYSTEM_TIME = CURRENT TIMESTAMP - 1 MONTH
```
Example 2: Set the CURRENT TEMPORAL SYSTEM_TIME special register to the null value.
```
   SET CURRENT TEMPORAL SYSTEM_TIME = NULL
```