INCREASE command

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Summary

Privileges
File manager
Function
Increases the space available for a Model 204 file, or the space available in one of the tables of a Model 204 file.

There are two forms of the increase command:

  • The INCREASE DATASETS command, which increases the datasets used by a Model 204 file, and increases the free pages (which are counted by the FREESIZE parameter.
  • The INCREASE command ("non-DATASET"), which increases the space available in one of the tables of a Model 204 file.

Syntax for INCREASE DATASETS

INCREASE {DATASETS [WITH] ddname [,ddname]...}

Where: ddname is the data set whose pages are to be allocated to free space.

Syntax notes

An INCREASE command must be issued in file context. That is, the current default must be a file, not a group.

Each ddname parameter can be separated by commas or by one or more blanks. A DD name, not a data set name, must be used in the command.

Syntax for INCREASE of a table

INCREASE {TABLEB n [DYNAMIC|DYN]} | {TABLED | TABLEE | TABLEX} n

Where:

  • n is the number of pages in free space to be assigned to the specified table. The value of n is in the range 1 through the value of the FREESIZE parameter (the number of unassigned pages available in the Model 204 file).

  • DYNAMIC (or DYN) specifies that Table B is to be increased even if the file is opened by other users and has requests compiled against it. This option is available from Model 204 V7.1 onwards.

Syntax notes

An INCREASE command must be issued in file context. That is, the current default must be a file, not a group.

Example

OPEN CARS update password INCREASE DATASETS WITH CARS1, CAR2, C3, CABC INCREASE TABLEB 500 DYNAMIC INCREASE TABLED 800

Usage notes

If it is required to expand FREESIZE by adding extra data sets to the file to support the increase of a table, then the INCREASE DATASETS command should precede the INCREASE command for Table B, Table D, Table E, or Table X.

You can assign additional pages from free space for use by either Table B (except for hash key files), Table D, Table E, or Table X. The size of Tables A and C cannot be changed without reorganizing the file.

You can issue INCREASE DATASETS, INCREASE TABLEB, INCREASE TABLED, INCREASE TABLEE, and INCREASE TABLEX commands without stopping a file and bumping all users out of the file. The file may be accessed or updated at the same time while the INCREASE command is processing.

However, Model 204 handles INCREASE processing only one type at a time in succession, not simultaneously. You cannot process an INCREASE DATASETS command and an INCREASE TABLEB command at the same time.

You can increase Table B, even when the file is open and has requests compiled against it, by using the DYNAMIC option. Without this option, an INCREASE TABLEB command processes only files that are not open by any other users or subsystems. There is a small performance penalty for MP/204 users: multiprocessing is stopped for a short time while internal changes are made.

Increasing and decreasing a file, the various tables that make up a file, and the relevant table parameters are explained in detail in the File management articles, such as Managing file and table sizes.

If you are increasing the size of a table in response to a file full condition (FISTAT X'08'), reset FISTAT to X'00' after performing the INCREASE command.

However, make sure that the FISTAT X'02' bit (File is physically inconsistent) is not set. Never reset FISTAT for a physically inconsistent file.

In Model 204 7.5 and later, the file full bit (FISTAT X'08') is automatically cleared in a TBO file if Table D is increased enough so that DSIZE is greater than or equal to DPGSRES+DPGSUSED.

Privileges required

To use the INCREASE command you must have update authority to the selected file. If the file is open for read-only access, the INCREASE command is rejected with the following message:

M204.1036: UPDATES NOT PERMITTED

The INCREASE command cannot be used to increase XSIZE from zero.

See also

  • Further information about the use of INCREASE, including issues concerning exclusive file access and increasing the number of file segments, can be found in the Managing file and table sizes article.
  • The DECREASE command can be used to return unused pages, increasing FREESIZE so they can be used for another file table.