IBM DB2 Manual page 559

processes. See also cursor
stabilityrepeatable read, and uncommitted
read.
rebind
The creation of a new application plan for
an application program that has been
bound previously. If, for example, you
have added an index for a table that your
application accesses, you must rebind the
application in order to take advantage of
that index.
rebuild
The process of reallocating a coupling
facility structure. For the shared
communications area (SCA) and lock
structure, the structure is repopulated; for
the group buffer pool, changed pages are
usually cast out to disk, and the new
structure is populated only with changed
pages that were not successfully cast out.
record The storage representation of a row or
other data.
record identifier (RID)
A unique identifier that DB2 uses to
identify a row of data in a table. Compare
with row identifier.
record identifier (RID) pool
An area of main storage that is used for
sorting record identifiers during
list-prefetch processing.
record length
The sum of the length of all the columns
in a table, which is the length of the data
as it is physically stored in the database.
Records can be fixed length or varying
length, depending on how the columns
are defined. If all columns are
fixed-length columns, the record is a
fixed-length record. If one or more
columns are varying-length columns, the
record is a varying-length record.
Recoverable Resource Manager Services
attachment facility (RRSAF)
A DB2 subcomponent that uses Resource
Recovery Services to coordinate resource
commitment between DB2 and all other
resource managers that also use RRS in a
z/OS system.
recovery
The process of rebuilding databases after
a system failure.
recovery log
A collection of records that describes the
events that occur during DB2 execution
and indicates their sequence. The
recorded information is used for recovery
in the event of a failure during DB2
execution.
recovery manager
A subcomponent that supplies
coordination services that control the
interaction of DB2 resource managers
during commit, abort, checkpoint, and
restart processes. The recovery manager
also supports the recovery mechanisms of
other subsystems (for example, IMS) by
acting as a participant in the other
subsystem's process for protecting data
that has reached a point of consistency.
A coordinator or a participant (or both),
in the execution of a two-phase commit,
that can access a recovery log that
maintains the state of the logical unit of
work and names the immediate upstream
coordinator and downstream participants.
recovery pending (RECP)
A condition that prevents SQL access to a
table space that needs to be recovered.
recovery token
An identifier for an element that is used
in recovery (for example, NID or URID).
RECP See recovery pending.
redo A state of a unit of recovery that indicates
that changes are to be reapplied to the
disk media to ensure data integrity.
reentrant code
Executable code that can reside in storage
as one shared copy for all threads.
Reentrant code is not self-modifying and
provides separate storage areas for each
thread. See also threadsafe.
referential constraint
The requirement that nonnull values of a
designated foreign key are valid only if
they equal values of the primary key of a
designated table.
referential cycle
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A set of referential constraints such that
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| each base table in the set is a descendent
of itself. The tables that are involved in a
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referential cycle are ordered so that each
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Glossary