15.00 - BLK - Teradata Database

Teradata Database Support Utilities

prodname
Teradata Database
vrm_release
15.00
category
Configuration
featnum
B035-1180-015K

BLK

Purpose  

The BLK (Block) command recognizes file system blocks and displays CI, WCI, DB, and WDB blocks based on the block code in the block header. For other types of blocks, the command indicates the block type. This command will also display DB or WDB blocks in Depot cylinders.

Syntax  

Note: The online help lists the display options (/P, /S, /M, /L, /H, /X, /V) as /dispopt. You can type the options at the beginning or end of the command.

 

Syntax Element

Description

/P

Positions to the block, but does not display it.

/S
/M
/L
/H
/X

The display options: Short, Medium, Long, Hex, and Extended. The display format depends on the block type. For descriptions of how the display options are applied to the different block types, see the associated commands:“CI” on page 112, “DB” on page 117, “WCI” on page 226, and “WDB” on page 229.

/V

Validates the block according to the block type, but does not display the block.

/C

For compressed data blocks, displays the uncompressed DB header information, including extended header information pertaining to data compression.

If the scoped DB is not compressed, the output is similar to the display when the /S option is used.

/Z

For compressed data blocks, displays:

  • the uncompressed DB header information, including extended header information pertaining to data compression.
  • a hex format display of the compressed data stored in the DB. If the /Z option is not used, the hex display shows the uncompressed data.
  • If the scoped DB is not compressed, the output is similar to the output when the /x option is used.

    cylid

    The 64-bit identifier of a cylinder, entered as a 16‑character hexadecimal number.

    sectornum

    The sector number of the entries to be displayed.

    sectorcount

    The number of sectors to examine, starting from sectornum, but not extending beyond the end of the cylinder. This can be used for either normal or Depot sectors. All blocks within this range are displayed.

    =

    Filer will use the most recently saved values for cylid, sectornum, or sectorcount.

    This option cannot be used unless input values have already been defined for cylid, sectornum, or sectorcount. For more information, see “Stored Input Values” on page 82.

    Usage Notes  

    If the requested sector is in a segment in memory, BLK displays the segment from memory. If the segment is not in memory, BLK attempts to locate and display the sector from the file system B-Tree structures.

    If the requested sector is currently not in use in the file system, the requested sectors are read directly from disk and displayed in hexadecimal format.

    The DB command is similar to BLK, except it displays only Data Block segments. For more information, see “DB” on page 117.