Database Administrator

Library cache is a part of the Shared pool, which is almost the most complex part of the Oracle memory structure. It mainly stores information about shared curosr (SQL) and PLSQL objects (functions, procedure, trigger, and the table, index, view,

1. To create a global DBLink, you must first confirm that you have the permission to create a dblink: Select * from user_sys_privs where privilege like upper ('% Database link %'); If not, you must use the sysdba role to grant permissions to

Recently, when using the listner of the previous server, the following error occurs: "The current link cannot be identified." I found a lot of information, but I was very helpless. Then I calmed down and thought that the client was not strong enough

In addition to add_months, you can also use INTERVAL: Connected to Oracle Database 11g Enterprise Edition Release 11.1.0.7.0 ConnectedAsXxpo SQL> SQL> SELECT to_char (SYSDATE,'Yyyy/MM/DD HH24: MI: ss') Now FROM dual; NOW ------------------

This problem is a headache. If you find that the previous solution is not working, you can find a new solution from the Internet.: InUbuntu 10.04 (Or a little earlier)Start, UBuntuUseUpstartReplace the traditional/sbin/initRun the service and set

Change the vip address of Oracle 10g RAC 1 from 192.168.2.11 to 192.168.2.13, And the vip address of rac2 from 192.168.2.12 to 192.168.2.14.I. Overview of software and hardware Environments Two redhet Enterprise-R4-U4 systems rac1 and rac2 are

Oracle network perimeter Configuration Supports three application connectionsC/S application connection: sqlplus sys/x2145637 @ orclJava application connectionWeb client application connection Supported protocolsTCP/IPTCP/IP with SSLNamed

Oracle 11g R2 explicitly states that export and import are no longer supportedReason for elimination: Import and Export speed is slowAlternative: Data Pump, speed increased by 5 times, but cannot be remotely imported or exported, only on the

Steps:1. Create a directory. You must create a directory before importing and exporting the directory.# Sqlplus/as sysdba> Create directory dump_dir as '/home/Oracle/dump ';Note: dump_dir points to the actual physical path/home/oracle/dump, and

Install MySQL 5.5.15 in CentOS 6.0 #! /Bin/bash# Mysql dependencyYum-y install gcc make gcc-c ++ ncurses-devel openssl-devel Wget http://dev.mysql.com/get/Downloads/MySQL-5.5/mysql-5.5.15.tar.gz/from/http://mysql.he.net/Wget

DBRef is a more formal specification for creating references between documents. DBRefs (generally) include a collection name as well as an object id. most developers only use DBRefs if the collection can change from one document to the next. if your

Data Processing DeclareV_cnt int;BeginSelect count (*) into v_cnt from table name where conditions for querying operation dataIf v_cnt> 0 then -- if a record exists Related Operations ElseRelated Processing--End if;End; Processing of fields

ORA-01502: index 'xxx. xxxx' or partition of such index is in unusable state. Solution: Log On With DBA and run the following script. -- Log On with the DBA permission and execute -- Fix all indexes in the UNUSABLE status and rebuild them.

Installing Oracle in Linux is not easy for new users. Of course, it is the same for me (for myself, I have never learned Linux ). When installing Oracle, the Oracle program will check some system configurations, and the network configuration is one

SQL> select file_id, tablespace_name, file_name, bytes/(1024*1024) as MB from dba_data_files where tablespace_name like 'test _ T % ';   FILE_ID TABLESPACE_NAME FILE_NAME MB ---------------------------------------------------------------------------

Query locked tables in Oracle Select -- l. *, o. owner object_owner, o. object_Name, mac. status, mac. oSUSEr, mac. machineTrunc (l. ctime/60, 0) mm, (l. ctime/60-trunc (l. ctime/60, 0) * 60 ss,L. sid, mac. SERIAL # serial, l. type, mac. osuser,

Brief process of installing Oracle 11G in 64-bit Ubuntu: 1: Set the environment Sudo apt-get install rpm libaio1 ksh libtool libstdc ++ 5 build-essential 2:Set directory structure and symbolic link Sudo ln-s/usr/bin/awk Sudo ln-s/usr/bin/rpm

1. parameter description Generally, the default value of db_block_size is 8 KB. From this perspective, the block size of the database is the same. However, Oracle can configure Multiple Block Sizes.   SYS @ anqing1 (rac1)> show parameter

1. Install XtraBackup If it is a 32-bit system, just put the content of xtrabackup0.9.zip in the bin directory of mysql. You can also compile the database together. Take 5.0.88 as an example:First download the source code:

Check memory and swap partition size# Grep MemTotal/proc/meminfo# Grep SwapTotal/proc/meminfo Check disk space size# Df-h Check the libaio package. CentOS 4.8 is not installed by default.Note: The error "ORA-12547: TNS: lost contact" is reported