statistics on the b-tree
Columns
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OPT_CMPR_PCTSAVE
percentage storage saving expected from optimal prefix compression
HEIGHT
height of the b-tree
BLOCKS
blocks allocated to the segment
NAME
name of the index
PARTITION_NAME
name of the index partition,if partitioned
LF_ROWS
number of leaf rows (values in the index)
LF_BLKS
number of leaf blocks in the b-tree
LF_ROWS_LEN
sum of the lengths of all the leaf rows
LF_BLK_LEN
useable space in a leaf block
BR_ROWS
number of branch rows
BR_BLKS
number of branch blocks in the b-tree
BR_ROWS_LEN
sum of the lengths of all the branch blocks in the b-tree
BR_BLK_LEN
useable space in a branch block
DEL_LF_ROWS
number of deleted leaf rows in the index
DEL_LF_ROWS_LEN
total length of all deleted rows in the index
DISTINCT_KEYS
number of distinct keys in the index
MOST_REPEATED_KEY
how many times the most repeated key is repeated
BTREE_SPACE
total space currently allocated in the b-tree
USED_SPACE
total space that is currently being used in the b-tree
PCT_USED
percent of space allocated in the b-tree that is being used
ROWS_PER_KEY
average number of rows per distinct key
BLKS_GETS_PER_ACCESS
Expected number of consistent mode block gets per row. This assumes that a row chosen at random from the table is being searched for using the index
PRE_ROWS
number of prefix rows (values in the index)
PRE_ROWS_LEN
sum of lengths of all prefix rows
OPT_CMPR_COUNT
optimal prefix compression count for the index