Database Administrator

There are already many examples of this error on the Internet. I will record it myself. Error: ORA-00845 after Oracle 11gR2 is started Rac1:/home/oracle> sqlplus/as sysdba; SQL * Plus: Release 11.2.0.3.0 Production onTue Feb 14 09:11:41

When installing the Oracle database, you need to set the following system kernel parameters for Oralce propulsion. These parameters are briefly described as follows (the parameter values are kept in the file/etc/sysctl. conf) Kernel. shmmax: the

Environment:OS: Red Hat Linux As 5DB: Oracle 10.2.0.4 The following describes how to simulate Incomplete recovery after archiving logs are lost.1. Back up the databaseRun {Allocate channel c1 device type disk;Allocate channel c2 device type

When user dbname is used, the speed is slow and the following message is displayed: Mysql> use dbnameReading table information for completion of table and column namesYou can turn off this feature to get a quicker startup with- Then it is stuck

Due to the installation problem of the AIX operating system, the default time zone is the end of the DCT, and the time zone ending with the DCT is the summer time system. At on January 1, March 11, the system will automatically move forward for one

View the current MySQL encoding: Mysql> show variables like \ '% character % \'; + -------------------------- + ---------------------------- + | Variable_name | Value | + -------------------------- + ---------------------------- + |

First, we will give an example by PAGE: Find the records from the first row to the Tenth row! Select c. * from (select a. *, rownum rm from oper_log a) c where c. rm between 1 and 10  Note: rownum is a pseudo column, which means a column that does

Original environment: AIX6.1 and Oracle CRS 11g R2 without DB soft. You need to install a new database and INSTANCE, and prepare to test, upgrade, and install PSU 11.2.0.3.2. During the DBCA process, the ASM disk cannot be identified. The solution

SQL Server 2000 creates a database with the same name, stops the database, deletes files, and Copies files. Start the database. In this case, the database has doubts. Open the query analyzer.Exec sp_configure 'Allow updates', 1 reconfigure with

1. Three types of Oralce logon authentication refer Operating system verification-my computer-management-local users and groups-group ora_dba Password File to verify that _ PWDorcl. ora under the installation directory of oralce is the

Theoretical analysis: 1) server process searches buffer cache for the block to be updated by update (also known as buffer in memory). If no block is found, it reads the buffer cache from disk. 2) server process constructs a group of change vectors

The log archiving mode of Oracle can effectively prevent instance and disk faults and is indispensable for database fault recovery. Because the initial installation mode of oracle is not the archive mode, therefore, you need to set it to archive

INACTIVELog corruption SQL> alter system switch logfile;  System altered. View the log status SQL>Select * from v $ log;   GROUP # THREAD # SEQUENCE # bytes members arc status FIRST_CHANGE # FIRST_TIM -------------------------------------------------

Check System Environment Grep MemTotal/proc/meminfo# Check physical memory Grep SwapTotal/proc/meninfo # Check the swap space Df-k# Checking Disks Environment required for installing OracleYum install-y binutils compat-db compat-libstdc ++

From MySQL5.6, a new parameter innodb_page_size can be set to 8 K and 4 K for Innodb data pages. The default value is 16 K. This parameter must be added to my. cnf at the beginning of initialization. If a table has been created and modified, an

The configuration of the Oracle RAC listener is slightly different from that of a single instance, but its principles and implementation methods are basically the same. In Oracle, the tns process is used to provide service registration for one or

1. The client cannot connect to the database. 2. Check that the database instance status is OPEN and alert_SID.log is correct. 3. The following information is displayed when you view the Database Listener: $ Lsnrctl status LSNRCTL for IBM/AIX assume

Converts a string to an array in Oracle and returns the array members at the specified position as needed. Create or replace function GetElementFromArrayByIndex (Liststr in varchar2, sPlitVal in varchar2, iPos integer) return varchar2 is/*Liststr --

1. Install Oracle asmlib Download the appropriate driver on oracle.com. The version must be the same as that of the operating system kernel. Currently, only the linux operating system has the asmlib package, and other systems do not. Asmlib

Special reminder before backup: 1.In the backupMySQLDatabaseMy. cnfFile,RequiredDatadir = {PATH },Otherwise, the path of the backup data cannot be found.. 2.During the backup processINNODBAfter the data file is backed up, the entire database is