Search notes:

Oracle: V$INDEXED_FIXED_COLUMN

v$indexed_fixed_column lists columns of fixed (X$) tables that are indexed.
select 
  ft.name,
  ic.column_name
from
  v$fixed_table            ft                                 join
  v$indexed_fixed_column   ic on ft.name = ic.table_name
order by
  ft.name,
  ic.index_number;
Github repository oracle-patterns, path: /Installed/dynamic-performance-views/indexed_fixed_column/column_name.sql

See also

x$kqfco lists all columns in X$ tables.
Oracle Dynamic Performance Views

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