SQLWKS> select owner from (select distinct owner, table_name from all_tab_columnss);
select owner from (select distinct owner, table_name from all_tab_columnss)
                                                          *
ORA- 00942 : table or view does not exist

SQLWKS> select owner from (select distinct owner, table_name from all/_tab_columnss);
select owner from (select distinct owner, table_name from all/_tab_columnss)
                                                          *
ORA- 00903 : invalid table name

SQLWKS> select owner from (select distinct owner, table_name from all_tab_columns) where rownum< 6 ;
OWNER                         
 ------------------------------
 
SYS                           
SYS                           
SYS                           
SYS                           
SYS  
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