IBM DB2 Manual page 536

points. Within a code page, each code
point has only one specific meaning. In
EBCDIC, for example, the character A is
assigned code point X'C1', and character
B is assigned code point X'C2'.
code point
In CDRA, a unique bit pattern that
represents a character in a code page.
code unit
The fundamental binary width in a
computer architecture that is used for
representing character data, such as 7 bits,
8 bits, 16 bits, or 32 bits. Depending on
the character encoding form that is used,
each code point in a coded character set
can be represented by one or more code
units.
coexistence
During migration, the period of time in
which two releases exist in the same data
sharing group.
cold start
A process by which DB2 restarts without
processing any log records. Contrast with
warm start.
collection
A group of packages that have the same
qualifier.
column
The vertical component of a table. A
column has a name and a particular data
type (for example, character, decimal, or
integer).
column function
See aggregate function.
"come from" checking
An LU 6.2 security option that defines a
list of authorization IDs that are allowed
to connect to DB2 from a partner LU.
command
A DB2 operator command or a DSN
subcommand. A command is distinct
from an SQL statement.
command prefix
A 1- to 8-character command identifier.
The command prefix distinguishes the
command as belonging to an application
or subsystem rather than to z/OS.
command recognition character (CRC)
A character that permits a z/OS console
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Application Programming Guide and Reference for Java
operator or an IMS subsystem user to
route DB2 commands to specific DB2
subsystems.
command scope
The scope of command operation in a
data sharing group.
commit
The operation that ends a unit of work by
releasing locks so that the database
changes that are made by that unit of
work can be perceived by other processes.
Contrast with rollback.
commit point
A point in time when data is considered
consistent.
common service area (CSA)
| In z/OS, a part of the common area that
contains data areas that are addressable
|
by all address spaces. Most DB2 use is in
|
| the extended CSA, which is above the
16-MB line.
|
communications database (CDB)
A set of tables in the DB2 catalog that are
used to establish conversations with
remote database management systems.
comparison operator
A token (such as =, >, or <) that is used
to specify a relationship between two
values.
compatibility mode* (CM*)
|
| A stage of the version-to-version
| migration process that applies to a DB2
subsystem or data sharing group that was
|
| in enabling-new-function mode (ENFM),
| enabling-new-function mode* (ENFM*), or
new-function mode (NFM) at one time.
|
| Fallback to a prior version is not
supported. When in compatibility mode*,
|
a DB2 data sharing group cannot coexist
|
| with members that are still at the prior
version level. Contrast with compatibility
|
mode, enabling-new-function mode,
|
| enabling-new-function mode*, and
new-function mode.
|
compatibility mode (CM)
|
The first stage of the version-to-version
|
| migration process. In a DB2 data sharing
group, members in compatibility mode
|
can coexist with members that are still at
|
| the prior version level. Fallback to the
prior version is also supported. When in
|
compatibility mode, the DB2 subsystem
|
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