13.7.4 Guidelines for the number of rows that are output for usage information for DB areas, tables, and indexes

The number of rows that are output for usage information for DB areas, tables, and indexes depends on the range subject to collection of information. The table below provides references to the subsections that contain the formulas for determining the number of rows that will be output. Use these formulas as guidelines, because they provide only approximate numbers of rows.

Title lines (column header rows) in the output results are not included in the row counts.

Table 13‒21: Ranges subject to information collection and the numbers of rows for usage information for DB areas, tables, and indexes
No.	Ranges subject to information collection for usage information for DB areas, tables, and indexes	-c option value	-n option value	Number of rows that are output (approximation)
1	Entire database (including tables and indexes in DB areas)^#	`dbarea` or omitted	--	See (1) Collecting the usage information for the entire database.
2	Specific DB area (including tables and indexes in the DB area)^#	`dbarea` or omitted	`DB-area-name`	See (2) Collecting the usage information for a specific DB area.
3	All tables^#	`table`	--	See (3) Collecting the usage information for all tables.
4	Specific table	`table`	`table-name`	See (4) Collecting the usage information for a specific table.
5	All indexes^#	`index`	--	See (5) Collecting the usage information for all indexes.
6	Specific index	`index`	`index-name`	See (6) Collecting the usage information for a specific index.

Legend:: --: The -n option is omitted.
Note: The master directory DB area and the work table DB area are not processed by the adbdbstatus command.
#: If a DB area does not store tables or indexes, only DB area usage is output. (Table and index usage is not output.) Furthermore, the information related to any DB area that does not store tables or indexes is output for the number of rows that equal the number of DB area files that comprise the DB area.

Organization of this subsection

(1) Collecting the usage information for the entire database
(2) Collecting the usage information for a specific DB area
(3) Collecting the usage information for all tables
(4) Collecting the usage information for a specific table
(5) Collecting the usage information for all indexes
(6) Collecting the usage information for a specific index

(1) Collecting the usage information for the entire database

You can use the formula shown below to obtain the approximate number of rows that are output when usage information for the entire database (including tables and indexes in the DB areas) is collected.

Formula (in rows)

[Figure]

Explanation of variables

table_inf_num: Number of table information items

Use the total of the numbers of DB area files in the DB areas that store tables for which usage information is to be collected. If a DB area stores multiple tables, include the number of DB area files for each table.
chunk_inf_num: Number of chunk information items

Obtain the value of the number of times the adbimport command with the -b option specified was executed minus one for each table for which usage information is to be output. Then set the sum of the obtained values in chunk_inf_num.

For a table for which the adbimport command with the -b option specified has never been executed, there is no need to obtain this value.
index_inf_num: Number of index information items

Use the total of the numbers of DB area files in the DB areas that store indexes for which usage information is to be collected. If a DB area stores multiple indexes, include the number of DB area files for each index.
dbarea_file_inf_num: Number of DB area information items

Use the total of the numbers of DB area files in the data DB areas, dictionary DB area, and system-table DB area.

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(2) Collecting the usage information for a specific DB area

You can use the formula shown below to obtain the approximate number of rows that are output when usage information for a specific DB area (including tables and indexes in the DB area) is collected.

Formula (in rows)

[Figure]

Explanation of variables

table_inf_num: Number of table information items

If the specified DB area stores tables, use the total of the number of DB area files in that DB area × the number of tables that are stored.
chunk_inf_num: Number of chunk information items

Obtain the value of the number of times the adbimport command with the -b option specified was executed minus one for each table for which usage information is to be output. Then set the sum of the obtained values in chunk_inf_num.

For a table for which the adbimport command with the -b option specified has never been executed, there is no need to obtain this value.
index_inf_num: Number of index information items

If the specified DB area stores indexes, use the total of the number of DB area files in that DB area × the number of indexes that are stored.
dbarea_file_inf_num: Number of DB area information items

Use the number of DB area files in the specified DB area.

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(3) Collecting the usage information for all tables

You can use the formula shown below to obtain the approximate number of rows that are output when usage information for all tables is collected.

Formula (in rows)

[Figure]

Explanation of variables

table_inf_num: Number of table information items

Use the total of the numbers of DB area files in the DB areas that store tables for which usage information is to be collected. If a DB area stores multiple tables, include the number of DB area files for each table.
chunk_inf_num: Number of chunk information items

Obtain the value of the number of times the adbimport command with the -b option specified was executed minus one for each table for which usage information is to be output. Then set the sum of the obtained values in chunk_inf_num.

For a table for which the adbimport command with the -b option specified has never been executed, there is no need to obtain this value.
dbarea_file_inf_num: Number of DB area information items

Use the total of the numbers of DB area files in the DB areas that store tables for which usage information is to be collected.

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(4) Collecting the usage information for a specific table

You can use the formula shown below to obtain the approximate number of rows that are output when usage information for a specific table is collected.

Formula (in rows)

[Figure]

Explanation of variables

table_inf_num: Number of table information items

Use the number of DB area files in the DB area that stores the specified table.
chunk_inf_num: Number of chunk information items

Use the number of times the adbimport command with the -b option specified was executed for the specified table minus one.

For a table for which the adbimport command with the -b option specified has never been executed, use 0.
dbarea_file_inf_num: Number of DB area information items

Use the number of DB area files in the DB area that store the specified table.

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(5) Collecting the usage information for all indexes

You can use the formula shown below to obtain the approximate number of rows that are output when usage information for all indexes is collected.

Formula (in rows)

[Figure]

Explanation of variables

index_inf_num: Number of index information items

Use the total of the numbers of DB area files in the DB areas that store indexes for which usage information is to be collected. If a DB area stores multiple indexes, include the number of DB area files for each index.
chunk_inf_num: Number of chunk information items

Obtain the value of the number of times the adbimport command with the -b option specified was executed minus one for each table that has indexes for which usage information is to be collected. Then set the sum of the obtained values in chunk_inf_num.

For a table for which the adbimport command with the -b option specified has never been executed, there is no need to obtain this value.
dbarea_file_inf_num: Number of DB area information items

Use the total of the numbers of DB area files in the DB areas that store indexes for which usage information is to be collected.

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(6) Collecting the usage information for a specific index

You can use the formula shown below to obtain the approximate number of rows that are output when usage information for a specific index is collected.

Formula (in rows)

[Figure]

Explanation of variables

index_inf_num: Number of index information items

Use the number of DB area files in the DB area that stores the specified index.
chunk_inf_num: Number of chunk information items

Use the number of times the adbimport command with the -b option specified was executed for the table for which the specified index was defined minus one. For a table for which the adbimport command with the -b option specified has never been executed, use 0.
dbarea_file_inf_num: Number of DB area information items

Use the total of the numbers of DB area files in the DB area that store the specified index.

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