清空某用户下所有表的记录

declare
 towner varchar2(30);
begin
  towner := '&user';
  /*
  先禁用表上所有的外键约束
  */
  for c in (select 'alter table '||owner||'.'||t.table_name || ' disable CONSTRAINT '||t.constraint_name as csql from all_constraints t where t.owner = towner  and t.constraint_type='R')
  loop
    begin
         execute immediate c.csql;
         dbms_output.put_line(c.csql|| '  ...........√');
         exception
            when others then
               dbms_output.put_line(c.csql||' ..........ⅹ');
    end;
 end loop;
 /*
 开始清理表数据
 */
 for c in (select owner,object_name,'truncate table '|| owner||'.'||object_name as dsql
            from all_objects  where object_type='TABLE'  and owner = towner) loop      
  begin                   
       
      
         execute immediate c.dsql;
         dbms_output.put_line(c.dsql || '  ...........√'); 
          exception
         when others then
             dbms_output.put_line(c.dsql||' ..........ⅹ');
   end;
  end loop;
 
  /*
  启用表上的外键约束
  */
  for c in (select 'alter table '||owner||'.'||table_name || ' enable CONSTRAINT '||t.constraint_name as csql from all_constraints t where t.owner = towner  and t.constraint_type='R')
  loop
    begin
         execute immediate c.csql;
         dbms_output.put_line(c.csql|| '  ...........√');
         exception
            when others then
               dbms_output.put_line(c.csql||' ..........ⅹ');
    end;
 end loop;
end;