今天在一个数据库上执行DBMS_METADATA包的时候，出现了ORA-19206的错误。

具体错误信息如下：

SQL> SELECT DBMS_METADATA.GET_DDL('MATERIALIZED_VIEW', 'CAT_AUTH_GMP', 'NDMAIN') FROM DUAL;

ERROR:

ORA-19206: Invalid value for query or REF CURSOR parameter

ORA-06512: at "SYS.DBMS_XMLGEN", line 83

ORA-06512: at "SYS.DBMS_METADATA", line 345

ORA-06512: at "SYS.DBMS_METADATA", line 410

ORA-06512: at "SYS.DBMS_METADATA", line 449

ORA-06512: at "SYS.DBMS_METADATA", line 615

ORA-06512: at "SYS.DBMS_METADATA", line 1221

ORA-06512: at line 1

no rows selected

仔细检查了一下，发现所有和物化视图相关的表在执行DBMS_METADATA.GET_DDL时都会出现上面的错误，而其他的对象并没有受到影响。

由于这个数据库的数据是通过EXP/IMP迁移得到的，虽然在IMP过程中没有什么明显的错误信息，但是仍然怀疑是EXP/IMP造成的数据字典出现了错误。

查询了一下METALINK信息，发现了很多类似的错误，而Oracle给出的解决方法是重装XDB。

于是尝试重装XML方案：

首先以SYSDBA身份登陆，关闭并重启数据库，为卸载XML对象做准备：

SQL> CONN / AS SYSDBA

Connected.

SQL> SHUTDOWN IMMEDIATE

Database closed.

Database dismounted.

ORACLE instance shut down.

SQL> STARTUP

ORACLE instance started.

Total System Global Area 5876197568 bytes

Fixed Size 739520 bytes

Variable Size 503316480 bytes

Database Buffers 5368709120 bytes

Redo Buffers 3432448 bytes

Database mounted.

Database opened.

SQL> SET ECHO ON

SQL> SPO XDB_REMOVAL.LOG

SQL> @?/rdbms/admin/catnoqm.sql

SQL> Rem

SQL> Rem $Header: catnoqm.sql 03-jan-2002.17:32:31 spannala Exp $

SQL> Rem

SQL> Rem catnoqm.sql

SQL> Rem

SQL> Rem Copyright (c) 2001, 2002, Oracle Corporation. All rights reserved.

SQL> Rem

SQL> Rem NAME

SQL> Rem catnoqm.sql - CATalog script. for removing (NO) XDB

SQL> Rem

SQL> Rem DESCRIPTION

SQL> Rem this script. drops the metadata created for SQL XML management

SQL> Rem This scirpt must be invoked as sys. It is to be invoked as

SQL> Rem

SQL> Rem @@catnoqm

SQL> Rem NOTES

SQL> Rem

SQL> Rem MODIFIED (MM/DD/YY)

SQL> Rem spannala 01/03/02 - tables are not handled by xdb

SQL> Rem spannala 01/02/02 - registry

SQL> Rem spannala 12/20/01 - passing in the resource tablespace name

SQL> Rem tsingh 11/17/01 - remove connection string

SQL> Rem tsingh 06/30/01 - XDB: XML Database merge

SQL> Rem amanikut 02/13/01 - Creation

SQL> Rem

SQL> Rem

SQL>

SQL> execute dbms_registry.removing('XDB');

BEGIN dbms_registry.removing('XDB'); END;

*

ERROR at line 1:

ORA-01403: no data found

ORA-06512: at "SYS.DBMS_REGISTRY", line 420

ORA-06512: at line 1

SQL> drop user xdb cascade;

User dropped.

SQL> SPO OFF

从上面脚本调用的结果可以确定，XML对象在执行导入时没有注册成功，可能这就是导致错误产生的原因。

保证JAVA池和共享池都大于150M，且XDB表空间可扩展，或者大于150M。则可以重启系统。

SQL> SHUTDOWN IMMEDIATE

Database closed.

Database dismounted.

ORACLE instance shut down.

SQL> STARTUP

ORACLE instance started.

Total System Global Area 5876197568 bytes

Fixed Size 739520 bytes

Variable Size 503316480 bytes

Database Buffers 5368709120 bytes

Redo Buffers 3432448 bytes

Database mounted.

Database opened.

下面重新安装XML方案：

SQL> SET ECHO ON

SQL> SPO XDB_INSTALL.LOG

SQL> @?/rdbms/admin/catqm.sql XDBPASSWD XDB TEMP

调用catqm.sql时，后面的三个参数依次时XDB用户的密码、默认表空间和临时镖客。

SQL> @?/rdbms/admin/catxdbj.sql

然后继续执行上面的SQL：

然后检查XDB用户是否存在错误对象，以及XDB是否注册到数据库中：

SQL> SELECT COUNT(*) FROM DBA_OBJECTS WHERE WNER = 'XDB' AND STATUS = 'INVALID';

COUNT(*)

----------

0

SQL> SELECT COMP_NAME, STATUS, VERSION FROM DBA_REGISTRY WHERE COMP_NAME = 'Oracle XML Database';

COMP_NAME STATUS VERSION

---------------------------------------- ----------- --------------------

Oracle XML Database VALID 9.2.0.4.0

下面重启数据库和监听，XDB重装完毕。

重建XDB之后，对DBMS_METADATA的访问恢复正常：

SQL> SELECT DBMS_METADATA.GET_DDL('MATERIALIZED_VIEW', 'CAT_AUTH_GMP', 'NDMAIN') FROM DUAL;

DBMS_METADATA.GET_DDL('MATERIALIZED_VIEW','CAT_AUTH_GMP','NDMAIN')

------------------------------------------------------------------

CREATE MATERIALIZED VIEW "NDMAIN"."CAT_AUTH_GMP"

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