This section provides the information required to use the program.
This section provides the information required to use the
CA Librarianis a highly sophisticated and flexible storage medium for source programs and other sets of data records, together with the collection of service routines for storing and retrieving them.
CA Librarianhelps you keep track of your programs and data. You can store anything as a member on an
CA Librarianmaster file, but
CA Librarianis most useful for source programs. It offers many features for auditing and control, and facilities to compile and run these programs.
The following documentation updates have been in the second edition of this documentation:
The basic component of
CA Librarianis its master file. A
masterfile is a pre-allocated area of space on disk where data is stored in a highly compressed format.
Each master file consists of one or more modules. A module is a collection of data records and the associated control information, identified by a single name. A data record can be any 80-byte record.
Traditional Master Files
CA Librariandisk master file is a direct-access data set consisting of fixed-length blocks. The block size is set when the master file is initialized. The file includes an index and a data area. Neither area is pre-allocated. The index expands as needed.
Modules are stored on the master file in a random manner. A free space map, located on the master file, keeps track of which blocks are in use and which are available.
CA Librariancan process an unlimited number of control statements in a disk master execution. Control statements are processed in the order of their appearance in the control deck. There are no work files required to process an
CA Librariandisk master.
Wide Record Master Files
The Wide Record Master File has the same external appearance as both DA and VSAM master files except for two major differences. A Wide Record Master File can support data records up to 32,760 bytes, and the archive level limit of 255 is no longer in effect. The archive level limit can be up to 99,999,999 levels.
All data records on an
CA Librarianmaster file are stored in a compressed format. This compression not only increases the capacity of the file, but also significantly shortens execution time by reducing the amount of I/O. The compression level of a master file is established at initialization time as either none, partial, or full compression. The length of a compressed record varies greatly according to its content. The following figure shows the full compression of a few typical COBOL source statements.
logical recordfor an
CA Librarianmaster file can contain several compressed data records.
CA Librarianthus makes maximum use of space to store the greatest amount of data.
COBOL Statement (80 columns)
Compressed Length (in bytes)
02 EMPL-NUM PICTURE 9(5)
MOVE INPUT-ACCOUNT TO MAST-ACCOUNT
ADD TWO TO LINE-COUNT
The Archiving Facility lets you recreate previous versions (or levels) of an updated module quickly and easily. When archiving is activated for a module,
CA Librarianretains in the module all records that would otherwise be deleted during an update operation.
As updates progress, the records are marked to indicate the level or levels where each record belongs. If you request an earlier level of a module, archiving reconstructs the level using the records marked as belonging to the specified level. The following figure shows the development of multiple levels in an archived module.
INITIAL FIRST SECOND MODULE Update: MODULE UPDATE: MODULE +------+ +--------+ +-------+ +--------+ +--------+ |010 A| |-REP ALL| |010 A | |-REP ALL| |010 AAA| |020 B| |010 A | |020 B | |010 AAA| |010 A | |030 C| |020 B | |030 CC| |030 CC | |020 B | |040 D| |030 CC | |030 C | |040 DD | |030 CC | |050 E| |040 DD | |040 DD| |050 E | |030 C | |060 F|-->|050 E |-->|040 D |-->|060 F |-->|040 DD | |070 G| |060 F | |050 E | |070 GG | |040 D | |080 H| |070 GG | |060 F | |080 HHH| |050 E | |090 I| |080 HH | |070 GG| |090 III| |060 F | |100 J| |090 I | |070 G | |100 J | |070 GG | +------+ |100 J | |080 HH| +--------+ |070 G | +--------+ |080 H | |080 HHH| |090 I | |080 HH | |100 J | |080 H | +-------+ |090 III| |090 I | Deleted or replaced records |100 J | retained in the module. +--------+
You can retain as many as 255 archiving levels for a single module. The current level number and the total number of levels being maintained for a module are reported on the Management Index listing. Wide Record Master Files have no archiving level limit.
You can access an earlier level of a module by specifying its absolute level number, its relative level number, or the date (or date and time) the level was current.
You must initialize a master file to support archiving, but an archived master file can contain both archived and non-archived modules.
You can examine the differences between two levels of an archived module residing on a disk master file through the COMPARE feature.
Note:Archiving affects other
CA Librarianoptions and facilities. Restrictions are noted in this guide where appropriate.