Glossary
- access method control block (ACB)
- A control block that links an application program (for example,
a CICS system) to VSAM or VTAM.
- alternate index
- For VSAM key-sequences data sets and entry-sequenced data sets,
an index of alternate keys that provides a path for secondary access
to the data set.
- bind
- The process by which the output from the SQL precompiler is converted
to a usable control structure, often called an access plan, application
plan, or package. During this process, access paths to the data are
selected and some authorization checking is performed.
- buffer pool
- Main storage that is reserved to satisfy the buffering requirements
for one or more DB2 table spaces or indexes.
- call attachment facility (CAF)
- A DB2 attachment facility for application programs that run in
TSO or MVS batch.
- copybook
- The definition of a record structure that describes the record
at a field level to an application program.
- data definition language (DDL)
- A set of SQL statements used to create DB2 objects.
- data migration component
- The CICS VT component that is used to perform the initial data
migration from VSAM to DB2.
- database request module (DBRM)
- A data set member that is created by the DB2 precompiler and that
contains information about SQL statements. DBRMs are used in the bind
process.
- data set definition module (DDM)
- A module that is used by CICS VT at run time to access the migrated
data in DB2. One DDM is created for each base cluster and alternate
index.
- data set information module (DIM)
- A module that defines the relationship between the VSAM record
structure and the DB2 table structure. One DIM is created for each
base cluster and alternate index path.
- data set table (DST)
- A CICS table that contains definition for all the VSAM data sets
that are migrated using CICS VT.
- entry-sequenced data set (ESDS)
- A VSAM data set whose records are physically in the same order
in which they were put in the data set. It is processed by addressed
direct access or addressed sequential access and has no index. New
records are added at the end of the data set.
- field build exit (FBE)
A user written program that CICS VT uses for field level
data reengineering.
- global user exit (GLUE)
- A point in a CICS module at which CICS can pass control to a user-written
program (known as an exit program), and then resume control when the
program has finished. CICS VT uses a GLUE to intercept VSAM calls
issued by programs running in CICS.
- installation verification procedure (IVP)
- The series of post-configuration tasks that are used to verify
that the set up and configuration of CICS VT has been successful.
- insert, replace delete exit (IRD)
- A user written program that CICS VT uses to perform record level
reengineering.
- Interactive System Productivity Facility (ISPF)
- An IBM licensed program that serves as a full-screen editor and
dialog manager. Used for writing application programs, it provides
a means of generating standard screen panels and interactive dialogs
between the application programmer and terminal user.
- job control language
- A control language that is used to describe a job and its requirements
to an operating system.
- Job Entry Subsystem (JES)
- An IBM licensed program that receives jobs into the system and
processes all output data that is produced by jobs.
- key-sequenced data set
- In a z/OS environment, a VSAM file or data set whose records are
loaded in key sequence and controlled by an index.
- library lookaside (LLA)
- A facility in MVS/ESA that reduces library I/O activity by keeping
selected directory entries in storage, instead of making repetitive
searches of DASD.
- mapping
- A CICS VT process that establishes the relationship between a
VSAM record and a DB2 row, in order to generate DIM and DDM run time
modules.
- mapping component
- The CICS VT ISPF component that is used to perform mapping.
- migration unit
- A number of VSAM data sets that are migrated at the same time.
- page set
- A table space or index space. Each page set consists of a collection
of VSAM data sets.
- primary index
- An index that enforces the uniqueness of a primary key.
- primary key
- In a relational database, a unique, non-null key that is part
of the definition of a table. A table cannot be defnied as a parent
unless it has a unique key or primary key.
- program list table (PLT)
- The CICS control table that contains a list of programs. The programs
in a PLT can be executed as a group during CICS start up or shutdown,
and can be enabled and disabled as a group by a single CEMT transaction.
- relative record data set (RRDS)
- A VSAM data set organization, in which records are of fixed length
and are accessed by their relative record numbers. The relative record
number (RRN) of a record is its displacement (in records) from the
beginning of the data set.
- relative record number (RRN)
- In an RRDS, the number of the "slot" used to hold a record, that
is its displacement (in records) from the beginning of the data set.
- run-time component
- The component of CICS VT that intercepts VSAM calls issued by
application programs and processes them in DB2.
- SQL Processor Using File Input (SPUFI)
- A facility of the TSO attachment subcomponent that enables the
DB2I user to execute SQL statements without embedding them in an application
program.
- storage group
- A named set of disks on which DB2 data can be stored.
- subsystem interface (SSI)
- The MVS interface by which routines request services of, or pass
information to, subsystems. The SSI is used by CICS VT to intercept
VSAM calls issued by batch programs.
- task-related user exit (TRUE)
- A user exit program that is associated with specified events in
a particular task, rather than with every occurrence of a particular
event in CICS processing (as is the case with global user exits).