select count(*) from v$locked_object;
select * from v$locked_object;

select b.owner,b.object_name,a.session_id,a.locked_mode from v$locked_object a,dba_objects b where b.object_id = a.object_id;

select b.username,b.sid,b.serial#,logon_time from v$locked_object a,v$session b where a.session_id = b.sid order by b.logon_time; 

alter table tb modify (name nvarchar2(20));

alter table sft_bfwo rename column bfwoid to wid;
alter table sft_bfwo add bfwoid char(16);
update sft_bfwo set bfwoid=trim(wid);
alter table sft_bfwo drop column wid;

create table table_name_new as select * from table_name_old

create table table_name_new as select * from table_name_old where 1=2;

create table table_name_new like table_name_old

insert into table_name_new select * from table_name_old

insert into table_name_new(column1,column2...) select column1,column2... from table_name_old