The DBA_IND_COLUMNS view provides information about all columns included in indexes on all tables in the database.

index_ownerTEXTUser name of the index owner.
schema_nameTEXTName of the schema in which the index belongs.
index_nameTEXTName of the index.
table_ownerTEXTUser name of the table owner.
table_nameTEXTName of the table in which the index belongs.
column_nameTEXTName of column or attribute of object column.
column_positionSMALLINTPosition of the column in the index.
column_lengthSMALLINTLength of the column in bytes.
char_lengthNUMERICLength of the column in characters.
descendCHARACTER(1)Included only for compatibility. Always set to Y (descending).