TABLEBX command

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Summary

Privileges
File manager
Function
Displays information about PAGE use in Tables B and X of a Model 204 file

Syntax

TABLEBX [LIST] [RECORD LENGTH | RECLEN] [OVERFLOW] [MASTER] [PAGE pagenumber] [PAGES pagenumber1 TO pagenumber2]

Where:

The following options display PAGE use in Tables B and X. A TABLEBX command accepts only one option per command, except if the LIST option is specified, which may be followed by the RECORD LENGTH option.

Option

Displays...

LIST

One line for each Table B and Table X page scanned, from the lowest to the highest page.

RECORD LENGTH

Average length of a logical record in Tables B. RECORD LENGTH can be abbreviated as RECLEN.

OVERFLOW

Table B averages for the overflow area of a sorted file.

MASTER

Table B averages for the master area of a sorted file.

pagenumber, pagenumber1, and pagenumber2

Specific pages in Table B.

PAGE

Table B averages for the specified file page.

PAGES

Table B averages for page number1 through page number2.

Examples

TABLEBX command output

You can display the space utilization of Tables B and X together by issuing a TABLEBX command.

TABLEBX 8 AVG. FREE SPACE PER PAGE 220 AVG. FREE SLOTS PER PAGE 1025 NUMBER OF PAGES PROCESSED 256 BRECPPG - TABLE B RECORDS PER PAGE 17 BRESERVE - TABLE B RESERVED SPACE PER PAGE 99 AVG. FREE SPACE PER PAGE 243 AVG. FREE SLOTS PER PAGE 8652 NUMBER OF PAGES PROCESSED 256 XRECPPG - TABLE X EXTENSION SLOTS PER PAGE 17 XRESERVE - TABLE X RESERVED SPACE PER PAGE

Usage notes

You can issue a TABLEBX command only in file context: that is, the current default must be a file, not a group.

TABLEBX command output can be routed to a USE data set.

If you specify a TABLEBX RECLEN x command, where x is something other than end-of-line, the following error is issued.

M204.0643: AN OPERAND IS INVALID OR MISSING

Using the TABLEBX command without any option provides only the averages over Tables B and X active pages. For a sorted file, the averages are computed separately for the overflow and master pages, and they appear separately in the output.

Using the LIST option

To get the exact amounts of free space and free slots on each active page, you must use the LIST option. This option produces a printed line for each Table B and Table X page scanned, starting with the lowest active page and ending with the highest one. The output of the LIST option, which precedes the averages shown above, is displayed in the following format:

PAGE NO. FREE SPACE FREE SLOTS nnn nnn nnn . . . . . . . . .

If the current file is a sorted one, each line includes an indication of the type of page that the line describes. For example, if page number 5 is an overflow page, the output might be:

PAGE NO. FREE SPACE FREE SLOTS 5 200 28 OVERFLOW

Limiting the range of pages scanned

You can limit the range of Table BX pages to be scanned in the following ways:

  • Specify the PAGE or PAGES option to select a single page or a range of pages.

    The following command causes a scan of five pages, if they fall in the range of active pages. If any of the selected pages is inactive, an error message is issued and the command is ignored. Page numbers are specified in decimal and cannot be negative. For example:

    TABLEBX PAGES 0 TO 4

  • Limit the range of pages scanned. This way applies only to sorted files. Use the options OVERFLOW or MASTER. In either case, the scan is done only over the specified pages.

Using the RECORD LENGTH option

The RECORD LENGTH option provides the average logical record length in Table B. A logical record is a record that includes all its extensions.

The average record length is exact unless DELETE RECORDS or IFDSET is used in the file. If DELETE RECORDS or IFDSET is used, the record length computed is too big, because space from the deleted records is never released.

The RECORD LENGTH option is available only when all of Tables B and X are scanned. Or, to state it another way, RECLEN option does not work with either the PAGE n or the PAGES n1 TO n2 option.