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The Oracle Database is crashing down in few minutes as soon as we start the Database. DB 11.2.0.4 in linux single instance . it is in VMWare 6, Done a dynamic disk allocation before the problem occurred . then check alert log found ORA-600 [kdBlkCheckError] and ORA-600[4194] errors.
Why is my database after running for some time , large number of database server processes will be created , but the number of sessions is very little, what actions cause orphaned processes? And sometimes hit ora-20 error..
很久前在国外的一个blog就看到说是oracle RDBMS(not NOSQL)要支持JSON, 当时说是XMLDB 开发组在做这个事情，随着oracle 12.1.0.2 release 得到确认，的确引入这一特性，JSON, JavaScript Ojbect Notation 在结构上和XML有很多相似之处, 而且这种Schema less data management的数据模型在NOSQL 中广泛应用，数据的存储相对更加紧凑，避免有时空列致ORACLE RDBMS中表一些数据”洞”…
ora-600 [kdsgrp1] 发生fetch 操作查找预期的行失败时, 常有ora-600 [qertbFetchByRowID] 伴随，这次遇到的一个aix 10.2.0.4 rac案例有 ora-7445 [kdr9ir2F0rst4srp0+0068] 和 ora-600 [25027], [6], [825242163] 陪伴, 而且 ora-600 [25027] 的rdba 莫名指向了一些不相干数据块..
ORA-39095 : ” dump file space has been exhausted. Unable to allocate 8192 bytes”
HOW do I fix the ORA-39095 error?
Answer:
There are several likely reasons for this error:…
The ORA-600 [KKMUPSVIEWDESTFRO_4] happens while running a merge statement with join elimination. Such join elimination can only happen if the fix for bug 7679164 is present and enabled. This fix was included in the 11.2.0.1 base release.
By default DBUA removes all the hidden parameters during upgrade.If you want to keep the hidden parametersinvoke DBUA with ‘keepHiddenParams’ option.e.g./dbua -keepHiddenParams
有一个procedure中一段SQL用到了synynom,而synonym指向一个dblink所对应的表，其中是两个子查询做了full join,在procedure 编译时提示ORA-00942: table or view does not exist，而把那段plsql 查询语句块拿出来，做为单条SQL执行时完全正常且有返回结果…
If you are grant privilege to new account like this “grant connect, resource to username”, as you know from 11g the role “Connect” only have “create session” privilege , but now in 12c ,the role “Resource” privilege had changed too.
接上一篇 http://www.anbob.com/archives/2323.html 下面我们从统计信息入手 sys@DEVDB>select count(distinct join_course_count),count(distinct is_course_qual),count(*) from app_zyyjhj.em_examinee; COUNT(DISTINCTJOIN_COURSE_COUNT) COUNT(DISTINCTIS_COURSE_QUAL) COUNT(*) ——————————– —————————– ——————– 6 4 35765 #使用tabstat2 脚本收信表信息，我已截断输出 sys@DEVDB>@tabstat2 em_examinee app_zyyjhj Table Number Empty Average Chain Average Global User Sample Date Name of Rows Blocks Blocks Space Count Row Len Stats Stats Size MM-DD-YYYY ————— ————– ——– ———— ——- ——– ——- —— —— … Read more
当CBO产生的Cardinality过低，尤其是在表之间关连时，往往会差之毫厘差之千里，甚至影响表之间的join方式，注意下MERGE JOIN CARTESIAN部分，这里使用了一种NL style的MJ,..
注意上面的4# 计划 的fileter 部分， 这就是问题的根源。了解SQL的执行步骤应该清楚在sql parse阶段CBO会帮我们做sql查询转换生成高效的执行计划, 在本案例我们想把TO_NUMBER(“S”.”SCORE”)<60 的条件放到子查询返回的结果集后再过滤, 结果CBO错误把此条件提前和该字段的其它条件一并执行..
RMAN Tablespace Point-In-Time Recovery ( TSPITR) enables you to quickly recover one or more tablespaces in an Oracle database to an earlier time, without affecting the state of the rest of the tablespaces and other objects in the database.
DBPITR enables you to recover a database to some time in the past.I will demonstrate below how to do flashback a database to a point in time.
A Question in QQ group get ins-30131 error when install oracle database 12c today, following error
[INS-30131] Initial setup required for the execution of installer validations failed
In the case ,the corrupted block was a index segment
ORA-01578: ORACLE data block corrupted (file # 47, block # 49)
ORA-01110: data file 47: ‘/dev/rdb…’
Rman backup fails with ORA-19566 error
A friend asked me ,they add new disk to a ASM diskgroup. Disks were added successfully. But when tried alter tablespace add new datafile using the diskgroup one the disks were recently added, they got “ora-01119” and “ORA-17502″,”ORA-15041” errors during add new datafile.
昨天DB 磁盘空间预警空间不足，发现临时表空间扩展的非常之大，于是规划调整临时表空间换个磁盘路径，本来online switch temp tablespace 并不难，结果还是遇到小问题..
ON single-instance 1, make sure asm diskgroup is avaliable Select name,total_mb,free_mb from v$asm_diskgroup where state=’CONNECTED’; 2, check current controlfile and using spfile show parameter control_files show parameter pfile 3, add new controlfile to spfile alter system set control_files='[original file]’,'[asm diskgroup name where new control file will stored]’ scope=spfile ; for example: alter system set control_files=’+OLD/ANBOB/controlfile/current.258.798205861′,’+NEW_DATA’ … Read more
自己画了个从oracle 7及后续版本升级到oracle 12c 的升级路线图。 另存为下载查看效果良好。