How Is the Database Space Information Calculated?

In write programs, the Archive Development Kit (ADK) automatically collects statistics. In delete, read, and reload programs, you must use ARCHIVE_GIVE_STATISTICS to pass statistical information to ADK. The statistics collected by ARCHIVE_GIVE_STATISTICS can be displayed as described in Statistics.

This function module can accept data for any of the six ABAP Dictionary object types:

·        TRANSP: Transparent table

·        POOL: Pooled table

·        VIEW: Database or projection view

·        CLUSTER: Cluster table

·        INTTAB: Structure, help view, maintenance view, or structure view

·        APPEND: Append structure

ADK calculates the database space according to the relevant ABAP Dictionary object type and uses the function module DDIF_TABL_GET to get the width of the relevant object.

You should note, however, that this width is not necessarily identical with the database space occupied by the object. If, for example, you are using a Unicode database with UTF-16 coding, then, n characters (width = n) in a character-type field occupy at least 2n bytes in the database.

After calculating the database space, ADK assigns each result to one of the following database space categories. These categories correspond to the categories in the Statistics function in Archive Administration. The DB Space is the sum of these four categories.

DB Table Space

ABAP Dictionary Object Type

Table Space =

TRANSP

width * number of records

POOL

width * number of records

VIEW

width * number of records

DB Index Space

ABAP Dictionary Object Type

Index Space =

TRANSP

(width of primary key fields + width of all secondary key fields) * number of records

POOL

width of primary key fields * number of records

VIEW

width of primary key fields * number of records

CLUSTER

width of primary key fields * number of records

DB Cluster Space

ABAP Dictionary Object Type

Cluster Space =

CLUSTER

width * number of records

DB Structure Space

ABAP Dictionary

Object Type

Structure Space =

INTTAB

width * number of records

APPEND

width * number of records

See Also

Function module documentation for ARCHIVE_GIVE_STATISTICS