IBM DB2 Manual page 556

parallelism coordinator
In Sysplex query parallelism, the DB2
subsystem from which the parallel query
originates.
Parallel Sysplex
A set of z/OS systems that communicate
and cooperate with each other through
certain multisystem hardware components
and software services to process customer
workloads.
parallel task
The execution unit that is dynamically
created to process a query in parallel. A
parallel task is implemented by a z/OS
service request block.
parameter marker
A question mark (?) that appears in a
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statement string of a dynamic SQL
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| statement. The question mark can appear
where a variable could appear if the
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statement string were a static SQL
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| statement.
parameter-name
An SQL identifier that designates a
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parameter in a routine that is written by a
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| user. Parameter names are required for
SQL procedures and SQL functions, and
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they are used in the body of the routine
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| to refer to the values of the parameters.
Parameter names are optional for external
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routines.
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parent key
A primary key or unique key in the
parent table of a referential constraint.
The values of a parent key determine the
valid values of the foreign key in the
referential constraint.
parent lock
For explicit hierarchical locking, a lock
that is held on a resource that might have
child locks that are lower in the hierarchy.
A parent lock is usually the table space
lock or the partition intent lock. See also
child lock.
parent row
A row whose primary key value is the
foreign key value of a dependent row.
parent table
A table whose primary key is referenced
by the foreign key of a dependent table.
540
Application Programming Guide and Reference for Java
parent table space
A table space that contains a parent table.
A table space containing a dependent of
that table is a dependent table space.
participant
An entity other than the commit
coordinator that takes part in the commit
process. The term participant is
synonymous with agent in SNA.
partition
A portion of a page set. Each partition
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| corresponds to a single, independently
| extendable data set. The maximum size of
a partition depends on the number of
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| partitions in the partitioned page set. All
| partitions of a given page set have the
same maximum size.
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partition-by-growth table space
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| A table space whose size can grow to
accommodate data growth. DB2 for z/OS
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manages partition-by-growth table spaces
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| by automatically adding new data sets
when the database needs more space to
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satisfy an insert operation. Contrast with
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| range-partitioned table space. See also
universal table space.
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partitioned data set (PDS)
A data set in disk storage that is divided
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| into partitions, which are called members.
Each partition can contain a program,
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part of a program, or data. A program
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| library is an example of a partitioned data
set.
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partitioned index
An index that is physically partitioned.
Both partitioning indexes and secondary
indexes can be partitioned.
partitioned page set
A partitioned table space or an index
space. Header pages, space map pages,
data pages, and index pages reference
data only within the scope of the
partition.
partitioned table space
A table space that is based on a single
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| table and that is subdivided into
partitions, each of which can be processed
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independently by utilities. Contrast with
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| segmented table space and universal table
space.
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partitioning index
An index in which the leftmost columns
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