PL/SQL执行存储过程
1、PL/SQL中SQL窗口执行过程：
BEGIN
DBMS_REDEFINITION.can_redef_table(uname => 'johnny', tname => 'BPM_TASK', options_flag => DBMS_REDEFINITION.cons_use_pk);
END;
2、PL/SQL中命令窗口执行过程：
EXEC DBMS_REDEFINITION.can_redef_table(uname => 'johnny&oracle账号#39;, tname => 'BPM_TASK', options_flag => DBMS_REDEFINITION.cons_use_pk);