INDEX_HISTOGRAM contains information from the ANALYZE INDEX ... VALIDATE STRUCTURE statement.
Note:
TheANALYZE INDEX ... VALIDATE STRUCTURE OFFLINE statement must be used in order to collect statistics.| Column | Datatype | NULL | Description | 
|---|---|---|---|
REPEAT_COUNT | 
NUMBER | 
Number of times that one or more index keys is repeated in the table | |
KEYS_WITH_REPEAT_COUNT | 
NUMBER | 
Number of index keys that are repeated that many times |