database - Oracle创建批处理作业时出错: already exists?

Question

我正在尝试在 Oracle 数据库中创建一个作业，每五分钟刷新一次物化 View 。以下是我编写的代码:

BEGIN
SYS.DBMS_SCHEDULER.create_job(
    job_name => 'refresh_cop_union',
    job_type => 'PLSQL_BLOCK',
    job_action => 'BEGIN DBMS_SNAPSHOT.REFRESH(''COP_UNION'',''C''); END;',
    start_date => SYSTIMESTAMP,
    repeat_interval => 'freq=minutely;interval=5',
    end_date => NULL,
    enabled => TRUE,
    auto_drop => FALSE,
    comments => 'Refresh COP_UNION matview'
);
END;
/

当我执行它时，出现以下错误:

Error report -
ORA-27477: "MASTER_DB"."REFRESH_COP_UNION" already exists
ORA-06512: at "SYS.DBMS_ISCHED", line 175
ORA-06512: at "SYS.DBMS_SCHEDULER", line 288
ORA-06512: at line 2
27477. 00000 - "\"%s\".\"%s\" already exists"
*Cause: An attempt was made to create an object with a name that has already been used by another object in the same schema.
*Action: Reissue the command using a different name or schema.

所以我的数据库中似乎有另一个同名的对象，可能是另一项工作。因此我尝试执行以下代码来删除它并用我的新版本替换它:

BEGIN
  sys.dbms_scheduler.drop_job(job_name => 'refresh_cop_union');
END;
/

但是失败并出现以下错误:

Error report -
ORA-27475: unknown job "MASTER_DB"."REFRESH_COP_UNION"
ORA-06512: at "SYS.DBMS_ISCHED", line 274
ORA-06512: at "SYS.DBMS_SCHEDULER", line 753
ORA-06512: at line 2
27475. 00000 - "unknown %s \"%s\".\"%s\""
*Cause: The specified object did not exist, privileges were not granted, or the object was of the wrong type.
*Action: Specify an object of the correct type on which you have privileges.

这基本上表明我尝试删除的对象不存在。这怎么可能？我怎样才能找到这个对象，看看它是什么并最终删除它？ 我还检查了数据库中可能具有相似名称的所有对象:其他表、 View 、触发器，但我什么也没发现。
我试图列出我拥有的所有工作，以便找到我的工作:

SELECT * FROM USER_JOBS
WHERE WHAT LIKE '%COP_UNION%';

但是什么也没出现。有什么想法吗？

Answer 1

您必须选择USER_SCHEDULER_JOBS，而不是USER_JOBS:

SELECT * 
FROM USER_SCHEDULER_JOBS
where JOB_NAME LIKE '%COP_UNION%';

DBMS_SCHEDULER 是(新)调度程序作业，而(旧)作业由包 DBMS_JOB 维护

看起来调度程序作业不得与任何其他对象同名。检查

SELECT * 
FROM ALL_OBJECTS 
WHERE OBJECT_NAME LIKE '%COP_UNION%';

并选择了不同的名称。

似乎是 Oracle 中的一个错误 ( Bug 4055853 )。根据 Oracle 的说法，解决方案/解决方法是

Changing the job name to be different than any object owned by the user will work around the problem.