INDEX_STATS

INDEX_STATS stores information from the last ANALYZE INDEX ... VALIDATE STRUCTURE statement.

Note:

The ANALYZE INDEX ... VALIDATE STRUCTURE OFFLINE statement must be used in order to collect statistics


Column Datatype NULL Description

HEIGHT

NUMBER

 

Height of the B-Tree

BLOCKS

NUMBER

NOT NULL

Blocks allocated to the segment

NAME

VARCHAR2(128)

NOT NULL

Name of the index

PARTITION_NAME

VARCHAR2(128)

 

Name of the partition of the index which was analyzed. If the index is not partitioned, NULL is returned.

LF_ROWS

NUMBER

 

Number of leaf rows (values in the index)

LF_BLKS

NUMBER

 

Number of leaf blocks in the B-Tree

LF_ROWS_LEN

NUMBER

 

Sum of the lengths of all the leaf rows

LF_BLK_LEN

NUMBER

 

Usable space in a leaf block

BR_ROWS

NUMBER

 

Number of branch rows in the B-Tree

BR_BLKS

NUMBER

 

Number of branch blocks in the B-Tree

BR_ROWS_LEN

NUMBER

 

Sum of the lengths of all the branch blocks in the B-Tree

BR_BLK_LEN

NUMBER

 

Usable space in a branch block

DEL_LF_ROWS

NUMBER

 

Number of deleted leaf rows in the index

DEL_LF_ROWS_LEN

NUMBER

 

Total length of all deleted rows in the index

DISTINCT_KEYS

NUMBER

 

Number of distinct keys in the index (may include rows that have been deleted)

MOST_REPEATED_KEY

NUMBER

 

How many times the most repeated key is repeated (may include rows that have been deleted)

BTREE_SPACE

NUMBER

 

Total space currently allocated in the B-Tree

USED_SPACE

NUMBER

 

Total space that is currently being used in the B-Tree

PCT_USED

NUMBER

 

Percent of space allocated in the B-Tree that is being used

ROWS_PER_KEY

NUMBER

 

Average number of rows per distinct key (this figure is calculated without consideration of deleted rows)

BLKS_GETS_PER_ACCESS

NUMBER

 

Expected number of consistent mode block reads per row, assuming that a randomly chosen row is accessed using the index. Used to calculate the number of consistent reads that will occur during an index scan.

PRE_ROWS

NUMBER

 

Number of prefix rows (values in the index)

PRE_ROWS_LEN

NUMBER

 

Sum of lengths of all prefix rows

OPT_CMPR_COUNT

NUMBER

 

Optimal index compression length

OPT_CMPR_PCTSAVE

NUMBER

 

Corresponding space savings after an ANALYZE