DB2 UDB for z/OS Version 8 Performance Topics - IBM Redbooks

Column Type Content
ACCESS_DEGREE SMALLINT The number of parallel tasks or
operations activated by a query.
ACCESS_PGROUP_ID SMALLINT The identifier of the parallel group for
accessing the new table.
JOIN_DEGREE SMALLINT The number of parallel operations or
tasks used in joining the composite
table with the new table.
JOIN_PGROUP_ID SMALLINT The identifier of the parallel group for
joining the composite table with the
new table.
- 34 Columns Format -Version 3
-Dec.1993-
- 34 Columns Format - Version 3
-Dec.1993-
SORTC_PGROUP_ID SMALLINT The parallel group identifier for the
parallel sort of the composite table.
SORTN_PGROUP_ID SMALLINT The parallel group identifier for the
parallel sort of the new table.
PARALLELISM_MODE CHAR(1) The kind of parallelism, if any, that is
used at bind time:
I Query I/O parallelism
C Query CP parallelism
X Sysplex query parallelism
MERGE_JOIN_COLS SMALLINT The number of columns that are
joined during a merge scan join
(Method=2).
CORRELATION_NAME CHAR(18) The correlation name of a table or
view that is specified in the statement.
PAGE_RANGE CHAR(1) NOT NULL WITH DEFAULT The table qualifies for page range
screening, so that plans scan only the
partitions that are needed. Y = yes
Blank =N
JOIN_TYPE CHAR(1) NOT NULL WITH DEFAULT -Type of join F, L, S, blank
GROUP_MEMBER CHAR(8) NOT NULL WITH DEFAULT member for EXPLAIN
IBM_SERVICE_DATA VARCHAR(254) NULL WITH
DEFAULT
-43 Columns Format - Version 4 -
Nov. 1995-
IBM use only
WHEN_OPTIMIZE CHAR(1) NOT NULL WITH DEFAULT -BIND, RUN
- 43 Columns Format -Version 4
-Nov. 1995-
QBLOCK_TYPE CHAR(6) NOT NULL WITH DEFAULT For each query block, an indication of
the type of SQL operation performed.
SELECT, INSERT, UPDATE...
BIND_TIME TIMESTAMP NULL WITH DEFAULT The time at which the plan or package
for this statement query block was
bound.
- 46 Column Format - Version 5 -
June 1997 -
- 46 Column Format - Version 5 -
June 1997-
Appendix D. EXPLAIN and its tables 413