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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(30) NOT NULL Name of the index
PARTITION_NAME VARCHAR2(30)   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 key compression length
OPT_CMPR_PCTSAVE NUMBER   Corresponding space savings after an ANALYZE