Description
The value of CURRENT DEGREE is replaced by the value of the
string constant or variable. The value must be a string with an actual length
that is not greater than 5 after trimming any leading and trailing blanks.
The value must be one of the following:
- 1
- No parallel processing is allowed.
- 2 through 32767
- Specifies the degree of parallelism that will be used.
- ANY
- Specifies that the database manager can choose to use any number of tasks for either
I/O or SMP parallel processing.
Use of parallel processing and the number
of tasks used is determined based on the number of processors available in
the system, this job's share of the amount of active memory available in the
pool in which the job is run, and whether the expected elapsed time for the
operation is limited by CPU processing or I/O resources. The database manager chooses
an implementation that minimizes elapsed time based on the job's share of
the memory in the pool.
- NONE
- No parallel processing is allowed.
- MAX
- The database manager can choose to use any number of tasks for either I/O or SMP
parallel processing. MAX is similar to ANY except the database manager assumes that all
active memory in the pool can be used.
- IO
- Any number of tasks can be used when the database manager chooses to use I/O parallel
processing for queries. SMP is not allowed.
- variable
- Specifies a variable that contains the value for the CURRENT DEGREE.
The variable:
- Must be a CHAR, VARCHAR, Unicode GRAPHIC, or Unicode VARGRAPHIC
variable. The actual length of the contents of the variable must
not be greater than 5 after trimming any leading and trailing blanks.
- Must not be the null value.
- All characters are case-sensitive and are not converted to uppercase characters.
- string-constant
- A character constant. The length of the constant must not exceed 5.
- DEFAULT
- If the PARALLEL_DEGREE parameter in a current query options
file (QAQQINI) is specified, the CURRENT DEGREE will be reset to the PARALLEL_DEGREE.
Otherwise, the CURRENT DEGREE will be reset from the degree specified by the
QQRYDEGREE system value.
(C) Copyright IBM Corporation 1992, 2006. All Rights Reserved.