The filter pushed in subquery issue in oracle 11G (filter推进子查询)
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..
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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.
The MegaRAID Storage Manager includes both GUI (MSM) and The megacli tool is used for managing the controller via the command-line interface, text based tools (MegaCLI) to monitor and manage the disk array.
What is it ?
a way to store files in your database that doesn’s suck.
a way to ensure that metadata is always kept with a file.
a way to get all the scaliing benefits of mongodb for files.
The following examples , I will demonstrate how to restore a backup MongoDB. mongoexport to export mongodb to json,csv format file, mongorestore to backup mongodb to BSON(Binary Serialized dOcumeNt format) File.
Default do not need username and password authenticate when access mongoDB ,I want to set up the user name & password for my mongoDB. so that any remote access will ask for the user name & password.
官网地址:http://www.mongodb.org; 1. Download the binary files for the desired release of MongoDB. wget http://124.202.164.12/files/113100000380F0C3/fastdl.mongodb.org/linux/mongodb-linux-x86_64-2.6.0.tgz 2. Extract the files from the downloaded archive. tar zxvf mongodb-linux-x86_64-2.6.0.tgz 3.Add new user ,Copy the extracted archive to the target directory. useradd mongo mkdir -p /mongodb mkdir -p /data/db chown -R mongo.mongo /mongodb chown -R mongo.mongo /data/db cp -R -n … Read more
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$asm_diskgroup where state=’CONNECTED’; 2, check current controlfile and using spfile show parameter control_files show parameter pfile 3, add new controlfile to spfile alter system set control_files='[original file]’,'[asm diskgroup name where new control file will stored]’ scope=spfile ; for example: alter system set control_files=’+OLD/ANBOB/controlfile/current.258.798205861′,’+NEW_DATA’ … Read more
this is shell script to backup mysql database, using mysqldump to dump all databases into separate files, and encrypt backup file using zip password option, Generate a collective file using tar, ftp to ftp server, to send email to DBA .
自己画了个从oracle 7及后续版本升级到oracle 12c 的升级路线图。 另存为下载查看效果良好。
With the annoucement of Oracle’s database support on RHEL6 and OEL6, they have decided to stop making ASMLIB for RHEL compatible kernels. ASMLIB is now only available if you are using Oracle Unbreakable Linux Kernel.But Recent events enabled Red Hat and Oracle to work togethe. Oracle ASMLib availability and support on Red Hat Enterprise Linux 6.
今天测式部门同事遇到的一个问题记录一下,开发库运行正常,同样的复制到测试库执行应用报错,
LINE/COL ERROR
——– —————————————————————–
59/5 PL/SQL: Statement ignored
59/23 PLS-00382: expression is of wrong type
EXP-00056: ORACLE error 24324 encountered
ORA-24324: service handle not initialized
ORA-07445: exception encountered: core dump [kgghstfel()+15] [SIGSEGV] [Address not mapped to object]
PROMPT List all SQL in the library cache cursor referencing a given table — Author: weejar — — you need to run this script either as SYS or — need to have relevant X$ proxy views created — I tested in oracle 11g it worked . undefine owner undefine table_name prompt accept owner prompt ‘Please … Read more
只是简单的记录主从的配置过程和一些常用排错方法 ,我本次安装使用的是mysql 5.6.16,和之前的老版本配置可能有些不同。