####检查依赖
Select b.table_name 主键表名,b.column_name 主键列名,a.table_name 外键表名,a.column_name 外键列名 From (Select a.constraint_name,b.table_name,b.column_name,a.r_constraint_name From user_constraints a,user_cons_columns b Where a.constraint_type = 'R' And a.constraint_name = b.constraint_name) a,(Select distinct a.r_constraint_name,b.column_name From user_constraints a,user_cons_columns b Where a.constraint_type = 'R' And a.r_constraint_name = b.constraint_name) b Where a.r_constraint_name = b.r_constraint_name
####检查被锁定的表
select object_name,machine,s.sid,s.serial# from v$locked_object l,dba_objects o,v$session s where l.object_id = o.object_id and l.session_id = s.sid;