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Message Posted: Mon, 20 Oct 2003 @ 18:53:35 GMT

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Hi,

This is what I posted back in March. This will give you an estimation of the space +- the number of AMPS since the values are rounded.

you have to have ROOT access to the NODEs ( or access to run DBW ) to run ferret.

Please make sure the DBA knows you are going to be running this and monitor it closely so that it doesn't affect the production work.

------

Hi,

If you don't mind a little math you can deduce the information from the SHOWBLOCKS command in Ferret.

Start the FERRET utility from the supervisor.

the default is to do every table on the system.

However, if you want you can select a SPECIFIC table you can specify

scope table "database.tablename" 0

Once setting the

then issue the showblocks command ( /s is the default )

showblocks /s { shows just the Primrary Data table )

showblocks /m { shows all the subtables including indexes on separate lines }

the show blocks display is quite wide and you need both sides of the display.

The left side of each line has the subtable id. ( this a /m display )

+------------
|
|
|
|  Table ID
|
+------------
|    0   135     <<<--- internal table id of selected table.
|
|       1024     <<<--- Primary data table
|       1028     <<<--- First secondary index
|       1032     <<<--- Second Secondary Index
|       2048     <<<---- Fallback data table from
|       2052     <<<---- fallback of First secondary index
|       2056     <<<---- Fallback of Second Secondary index
+------------

If you have more than 2 amps per fallback cluster you may see 3072, and 4096 and so on subtables as well.

at the right side of the of the display you will find.

+-----------------+-----------+-----------+
|   Data block    |   Total   |   Total   |
| size statistics |   Number  |   Number  |
+    (sectors)    |     of    |     of    |
|-----+-----+-----+    Data   | Cylinders |
| Min | Avg | Max |   Blocks  |           |
+-----+-----+-----+-----------+-----------+
                              |           |
+-----+-----+-----+-----------+-----------+
|  39 |  74 | 112 |        25 |         4 |
|  11 |  11 |  11 |         2 |         2 |
|  17 |  18 |  19 |         2 |         2 |
|  39 |  74 | 112 |        25 |         6 |
|  11 |  11 |  11 |         2 |         2 |
|  17 |  18 |  19 |         2 |         2 |
+-----+-----+-----+-----------+-----------+

        ^^^^        ^^^^^^^^^^
        ||||        ||||||||||

multiply the AVG datablock size by the Total number of Datablocks.

so following the 1024 (primary data table) line accross we would get

74 * 25 = 1850 sectors
1850 sectors * 512 bytes per sector = 947200 bytes.

you can do the same for the index subtables to get their sizes as well.

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