IBM DB2 Manual page 563

A collection of, and a way of qualifying,
database objects such as tables, views,
routines, indexes or triggers that define a
database. A database schema provides a
logical classification of database objects.
scrollability
The ability to use a cursor to fetch in
either a forward or backward direction.
The FETCH statement supports multiple
fetch orientations to indicate the new
position of the cursor. See also fetch
orientation.
scrollable cursor
A cursor that can be moved in both a
forward and a backward direction.
search condition
A criterion for selecting rows from a table.
A search condition consists of one or
more predicates.
secondary authorization ID
An authorization ID that has been
associated with a primary authorization
ID by an authorization exit routine.
secondary group buffer pool
For a duplexed group buffer pool, the
structure that is used to back up changed
pages that are written to the primary
group buffer pool. No page registration or
cross-invalidation occurs using the
secondary group buffer pool. The z/OS
equivalent is new structure.
secondary index
A nonpartitioning index that is useful for
enforcing a uniqueness constraint, for
clustering data, or for providing access
paths to data for queries. A secondary
index can be partitioned or
nonpartitioned. See also data-partitioned
secondary index (DPSI) and
nonpartitioned secondary index (NPSI).
section
The segment of a plan or package that
contains the executable structures for a
single SQL statement. For most SQL
statements, one section in the plan exists
for each SQL statement in the source
program. However, for cursor-related
statements, the DECLARE, OPEN,
FETCH, and CLOSE statements reference
the same section because they each refer
to the SELECT statement that is named in
the DECLARE CURSOR statement. SQL
statements such as COMMIT,
ROLLBACK, and some SET statements do
not use a section.
security label
|
A classification of users' access to objects
|
| or data rows in a multilevel security
environment."
|
segment
A group of pages that holds rows of a
single table. See also segmented table
space.
segmented table space
A table space that is divided into
equal-sized groups of pages called
segments. Segments are assigned to tables
so that rows of different tables are never
stored in the same segment. Contrast with
partitioned table space and universal table
space.
self-referencing constraint
A referential constraint that defines a
relationship in which a table is a
dependent of itself.
self-referencing table
A table with a self-referencing constraint.
sensitive cursor
A cursor that is sensitive to changes that
are made to the database after the result
table has been materialized.
sequence
A user-defined object that generates a
sequence of numeric values according to
user specifications.
sequential data set
A non-DB2 data set whose records are
organized on the basis of their successive
physical positions, such as on magnetic
tape. Several of the DB2 database utilities
require sequential data sets.
sequential prefetch
A mechanism that triggers consecutive
asynchronous I/O operations. Pages are
fetched before they are required, and
several pages are read with a single I/O
operation.
serialized profile
A Java object that contains SQL
statements and descriptions of host
variables. The SQLJ translator produces a
serialized profile for each connection
context.
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Glossary