SPA的整体测试过程可以参考:
故障描述:数据库字符集:US7ASCII,在SPA分析阶段正常,但在取报告阶段xml解析失败,具体现象如下:
SQL>
ALTER SESSION SET EVENTS='31156 TRACE NAME CONTEXT FOREVER, LEVEL 0X400';
SET LINES 1111 PAGES 50000 LONG 1999999999 TRIM ON TRIMS ON SERVEROUTPUT ON SIZE UNLIMITED
SPOOL error.html
SELECT XMLTYPE(DBMS_SQLPA.REPORT_ANALYSIS_TASK('SPA_TASK_201806','HTML','ERRORS','ALL',NULL,1000,'COMPARE_ET_201806')).GETCLOBVAL(0,0) FROM DUAL;
spool off
ERROR:
ORA-31011: XML parsing failed
ORA-19202: Error occurred in XML processing
LPX-00216: invalid character 207 (0xCF)
Error at line 26
ORA-06512: at "SYS.DBMS_SQLTUNE_INTERNAL", line 8211
ORA-06512: at "SYS.DBMS_SQLPA", line 515
ORA-06512: at line 1
这个invalid character 207,之前是别的无效字符,用一些方法删除掉重新SPA解包分析,又会报207无效字符,看起来是大量不合规的sql_text,基本判定删不完,而且就算能删除干净也会导致SPA的分析结果集缺失严重,所以我们需要更好的解决方案。 经过系列测试,和几位专家沟通,最终决定尝试独立恢复出这个库,测试修改字符集,参考命令如下:
SQL>
shutdown immediate;
startup mount;
select logins, active_state from v$instance;
alter system enable restricted session;
alter system set job_queue_processes=0;
alter database open;
select userenv('language') from dual;
--alter database character set zhs16gbk;
--注意:Oracle转化字符集
alter database character set internal_convert zhs16gbk;
--注意:Oracle会自动转换含有CLOB的
--alter database character set internal_use us7ascii;
--注意:Oracle会强制转换,会造成部分数据乱码,慎用
--alter database national character set zhs16gbk;
--注意:修改国家字符集,我这里不需要修改。
shutdown immediate;
startup
select userenv('language') from dual;
select logins, active_state from v$instance;
alter system disable restricted session;
alter system set job_queue_processes=1000;
再次尝试获取SPA报告:
ALTER SESSION SET EVENTS='31156 TRACE NAME CONTEXT FOREVER, LEVEL 0X400';
SET LINES 1111 PAGES 50000 LONG 1999999999 TRIM ON TRIMS ON SERVEROUTPUT ON SIZE UNLIMITED
SPOOL error.html
SELECT XMLTYPE(DBMS_SQLPA.REPORT_ANALYSIS_TASK('SPA_TASK_201806','HTML','ERRORS','ALL',NULL,1000,'COMPARE_ET_201806')).GETCLOBVAL(0,0) FROM DUAL;
spool off
可以成功执行取出报告。
另外注意,字符集不能反复修改,实际测试,如果此时改成us7ascii,再改回zhs16gbk,再尝试取SPA报告也不再成功。我这里测试会有如下的报错:
ERROR:
ORA-51705: XML DOM error: 217 "
LPX-00217: invalid character 0 (U+0000)"
ORA-06512: at "SYS.DBMS_SQLTUNE_INTERNAL", line 8211
ORA-06512: at "SYS.DBMS_SQLPA", line 515
ORA-06512: at line 1
所以,这也是为什么要RMAN恢复一个独立的测试库进行取报告的原因。