しらなかった。。。
SQL> create table tab1 as select * from v$parameter; Table created. SQL> create index tab1i1 on tab1 (num); Index created. SQL> col OWNER for a10 SQL> col SEGMENT_NAME for a10 SQL> select OWNER,SEGMENT_NAME,EXTENTS from dba_segments where owner='G'; OWNER SEGMENT_NA EXTENTS ---------- ---------- ---------- G TAB1 2 G TAB1I1 1 SQL> alter index tab1i1 unusable; Index altered. SQL> select OWNER,SEGMENT_NAME,EXTENTS from dba_segments where owner='G'; OWNER SEGMENT_NA EXTENTS ---------- ---------- ---------- G TAB1 2 SQL>
索引(TAB1I1)のセグメントが、DBA_SEGMENTS が消えてる。