6.210 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