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 INDEXSTATISTICS 

The statistics system table INDEXSTATISTICS contains information about the structure and sizes of indexes.

INDEXSTATISTICS

OWNER

CHAR(32)

Table owner

TABLENAME

CHAR(32)

Table name

INDEXNAME

CHAR(32)

Index name (NULL for unknown indexes)

COLUMNNAME

CHAR(32)

Name of an inverted column

DESCRIPTION

CHAR(40)

Description (see table Column DESCRIPTION) of how to interpret following columns

CHAR_VALUE

CHAR(12)

Alphanumeric value

NUMERIC_VALUE

FIXED(10)

Numeric value

Column DESCRIPTION

Value

Explanation

Root pno

NUMERIC_VALUE contains the page number of the root of the B* tree

Filetype

CHAR_VALUE contains the type of the B* tree

Used pages

NUMERIC_VALUE indicates how many pages are used by the index

Index pages

NUMERIC_VALUE indicates how many pages are used by the index in the B* tree index

Leaf pages

NUMERIC_VALUE indicates how many leaf pages are used by the index

Index levels

NUMERIC_VALUE contains the number of index levels in the B* tree

Space used in all pages(%)

NUMERIC_VALUE contains the used space of all pages in the B* tree (as a percentage)

Space used in root page(%)

NUMERIC_VALUE contains the used space of the root page in the B* tree (as a percentage)

Space used in index pages(%)

NUMERIC_VALUE contains the used space of the index pages in the B* tree (as a percentage)

Space used in index pages(%) min

NUMERIC_VALUE contains the minimum used space of the index pages in the B* tree (as a percentage)

Space used in index pages(%) max

NUMERIC_VALUE contains the maximum used space of the index pages in the B* tree (as a percentage)

Space used in leaf pages(%)

NUMERIC_VALUE contains the used space of the leaf pages in the B* tree (as a percentage)

Space used in leaf pages(%) min

NUMERIC_VALUE contains the minimum used space of the leaf pages in the B* tree (as a percentage)

Space used in leaf pages(%) max

NUMERIC_VALUE contains the maximum used space of the leaf pages in the B* tree (as a percentage)

Secondary keys (index lists)

NUMERIC_VALUE contains the number of different values of the indexed columns

Avg secondary key length

NUMERIC_VALUE contains the average length of an index value

Min secondary key length

NUMERIC_VALUE contains the minimum length of an index value

Max secondary key length

NUMERIC_VALUE contains the maximum length of an index value

Avg separator length

NUMERIC_VALUE contains the average length of a separator in the B* tree

Min separator length

NUMERIC_VALUE contains the minimum length of a separator

Max separator length

NUMERIC_VALUE contains the maximum length of a separator

Primary keys

NUMERIC_VALUE contains the number of rows in the table identified by OWNER and TABLENAME

Avg primary keys per list

NUMERIC_VALUE contains the average number of keys for each invert list

Min primary keys per list

NUMERIC_VALUE contains the minimum number of keys for each invert list

Max primary keys per list

NUMERIC_VALUE contains the maximum number of keys for each invert list

Values with selectivity <= 1%

NUMERIC_VALUE contains the number of invert lists with a selectivity <= 1%

Values with selectivity <= 5%

NUMERIC_VALUE contains the number of invert lists with a selectivity between 1% and 5%

Values with selectivity <= 10%

NUMERIC_VALUE contains the number of invert lists with a selectivity between 5% and 10%

Values with selectivity <= 25%

NUMERIC_VALUE contains the number of invert lists with a selectivity between 10% and 25%

Values with selectivity > 25%

NUMERIC_VALUE contains the number of invert lists with a selectivity > 25%

 

 

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