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Oracle: COL_USAGE$

COL_USAGE$ stores data that is required by dbms_stats to determine for which columns histograms need to be created when gathering column statistics.

COL_USAGE$ is maintained by SMON. Apparently, SMON can be triggered to update the table by calling

begin
   dbms_stats.flush_database_monitoring_info;
end;
/

select
   own.name owner,
   obj.name obj_name,
   col.name col_name,
   col.type#,
   col.length,
   col.precision#,
   col.scale,
   col.null$,
   cou.equality_preds,
   cou.equijoin_preds,
   cou.nonequijoin_preds,
   cou.range_preds,
   cou.like_preds,
   cou.null_preds,
   cou.timestamp,
   cou.flags
/* col.deflength,
   col.default$,
   col.intcol#,
   col.property,
   col.charsetid,
   col.charsetform,
   col.evaledition#,
   col.unusablebefore#,
   col.unusablebeginning#,
   col.acdrrescol#,
   col.collid,
   col.collintcol#,
   col.fixedstorage,
   col.spare1, col.spare2, col.spare3, col.spare4, col.spare5, col.spare6, col.spare7, col.spare8, col.spare9, col.spare10, col.spare11, col.spare12, col.spare13
  */
from
   sys.obj$       obj                                    join
   sys.user$      own  on obj.owner# = own.user#         join
   sys.col$       col  on obj.obj#   = col.obj#     left join
   sys.col_usage$ cou  on col.obj#   = cou.obj# and
                          col.col#   = cou.intcol#
where
   own.name = 'RENE' and
   obj.name = 'TQ84_COL_USAGE_TEST';

Oracle: COL_USAGE$

See also