15.00 - PREV - Teradata Database

Teradata Database Support Utilities

Teradata Database



The PREV command displays a previous row, WAL log record, DB, WDB, DBD, WDBD, CI, WCI, CID, WCID or subtable.


Note: You can type /dispopt or /rowopt at the beginning or end of the command.


Syntax Element



The display options, which are listed below.









Setting Selection






show a short formatted display of the object. This is the default.





show a medium-length formatted display of the object.





show a long formatted display of the object.





show a hexadecimal display of the object.





show an extended display of the object.





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.





    The row options, which are listed below.









    Setting Selection






    Positions to the physical rows or table requested. At least one physical row must be in the selected range. Nothing is displayed unless there is a problem.

    Physical rows store one of several types of data, such as regular table row data or column partition data.




    /C or /S

    Count the number of physical rows selected. This is the default for all subtables except the table header subtable.




    /I or /M

    Displays only the row header information (length, RowID, and flags).




    /L or /R

    Display the formatted row header and the fields in the physical row. This option is the default for the table header subtable. However, this option will not be the default formatted field display because the table header subtable is a special row format and requires special formatting.





    Display the entire physical row in hexadecimal, including the row header.





    The number of objects to display, starting with the object just previous to the beginning of the current context.

    The default is 1.


    Usage Notes  

    If number is specified, PREV displays previous objects of the same type until the requested number is reached. PREV sets the context to the objects displayed.

    If a whereclause is saved in the context, PREV will apply the conditions of the whereclause. For more information about the whereclause, see “DISPLAY” on page 127 and “Specifying a WHERE clause” on page 85.

    PREV displays the objects previous to the beginning of the current context as shown in the following table.


    From …

    PREV displays …

    row context

    previous rows within the table.

    table context (whether a subset of rows was displayed or ALL)

    previous subtables.

    DB context

    previous DBs.

    DBD context

    previous DBDs.

    CI context

    previous CIs.

    CID context

    previous CIDs.

    WAL log record context

    previous WAL log records.

    WDB context

    previous WDBs.

    WDBD context

    previous WDBDs.

    WCI context

    previous WCIs.

    WCID context

    previous WCIDs.