INDEXSTATISTICS
This
statistical system table contains information about structure and size of indexes.INDEXSTATISTICS
|
OWNER |
CHAR ( 32) |
Owner of a table |
|
TABLENAME |
CHAR ( 32) |
table name |
|
INDEXNAME |
CHAR ( 32) |
index name (NULL for unnamed indexes) |
|
COLUMNNAME |
CHAR ( 32) |
name of an inverted column |
|
DESCRIPTION |
CHAR ( 40) |
Description of how to interpret the following columns (see Column DESCRIPTION table) |
|
CHAR_VALUE |
CHAR ( 12) |
Alphanumeric value |
|
NUMERIC_VALUE |
FIXED (10) |
Numeric value |
DESCRIPTION column
|
Value |
Explanation |
|
Root pno |
NUMERIC_VALUE contains the page number of the B* tree root |
|
FILETYPE |
CHAR_VALUE contains the B* tree type |
|
Used pages |
NUMERIC_VALUE contains the number of pages used by the index |
|
Index pages |
NUMERIC_VALUE contains the number of B* tree index pages used by the index |
|
Leaf pages |
NUMERIC_VALUE contains the number of leaf pages used by the index |
|
Index levels |
NUMERIC_VALUE contains the number of B* tree index levels |
|
Space used in all pages(%) |
NUMERIC_VALUE contains the percentage of the B* tree root page used |
|
Space used in root page(%) |
NUMERIC_VALUE contains the percentage of the B* tree root page used |
|
Space used in index pages(%) |
NUMERIC_VALUE contains the percentage of the B* tree index pages used |
|
Space used in index pages(%) min |
NUMERIC_VALUE contains the minimum percentage of the B* tree index pages used |
|
Space used in index pages(%) max |
NUMERIC_VALUE contains the maximum percentage of the B* tree index pages used |
|
Space used in leaf pages(%) |
NUMERIC_VALUE contains the percentage of the B* tree leaf pages used |
|
Space used in leaf pages(%) min |
NUMERIC_VALUE contains the minimum percentage of the B* tree leaf pages used |
|
Space used in leaf pages(%) max |
NUMERIC_VALUE contains the maximum percentage of the B* tree leaf pages used |
|
Secondary keys (index lists) |
NUMERIC_VALUE contains the number of different values in the indexed columns |
|
Avg secondary key length |
NUMERIC_VALUE contains the average length of the index values |
|
Min secondary key length |
NUMERIC_VALUE contains the minimum length of the index values |
|
Max secondary key length |
NUMERIC_VALUE contains the maximum length of the index values |
|
Avg separator length |
NUMERIC_VALUE contains the average length of a B* tree separator |
|
Min separator length |
NUMERIC_VALUE contains the minimum length of the separator |
|
Max separator length |
NUMERIC_VALUE contains the maximum length of the separator |
|
Primary keys |
NUMERIC_VALUE contains the number of rows in the tables identified by OWNER and TABLENAME |
|
Avg primary keys per list |
NUMERIC_VALUE contains the average number of keys per index list |
|
Min primary keys per list |
NUMERIC_VALUE contains the minimum number of keys per index list |
|
Max primary keys per list |
NUMERIC_VALUE contains the maximum number of keys per index list |
|
Values with selectivity <= 1% |
NUMERIC_VALUE contains the number of index lists with a selectivity <= 1% |
|
Values with selectivity <= 5% |
NUMERIC_VALUE contains the number of index lists with a selectivity between 5% and 1% |
|
Values with selectivity <= 10% |
NUMERIC_VALUE contains the number of index lists with a selectivity between 10% and 5% |
|
Values with selectivity <= 25% |
NUMERIC_VALUE contains the number of index lists with a selectivity between 10% and 25%. |
|
Values with selectivity > 25% |
NUMERIC_VALUE contains the number of index lists with a selectivity > 25% |