INDEX_STATS stores information from the last ANALYZE INDEX ... VALIDATE STRUCTURE statement.
Note:
TheANALYZE 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 |