Database Administrator

When building a web application in Linux, You need to remotely access the MySQL database. We do not recommend using root in Linux to log on, but to add new users. 1) Log On As A root user# Mysql-u root-p 2) Insert a new user, host: %; user: jason;

When our Oracle Server is a Linux/Unix system, we want to use the EM tool to start oracle to learn about some system information from windows or other clients. You can use the following method: Open a window on the server and enter the following

RAID, a Redundant Array of cheap disks, is a method of storing the same data in different locations on multiple hard disks. RAID has many different types (called RAID "level"). Each type has its own advantages and disadvantages.　　For Oracle9i

When MySQL becomes the database of more and more web2 sites, when the site is getting bigger and bigger, the traffic is increasing, and the number of users is increasing, the database is often the first to become the bottleneck of the system, how to

I have been fully transferred to Linux. In the past, some services and databases under windows had to be transferred step by step. Apache, tomcat, jboss, and so on are easy to handle, that is, mysql has been tossing for 2 or 3 days. It is mainly

1. KeywordsAuto_increment 2. Auto-increment usageExample:Create table animals (id mediumint not null auto_increment,Name char (30) not null,Primary key (id )); 3. Auto-Increment Q: How to obtain the current maximum auto-increment value?A: select @

1. Download the four required rpm installation packages from the mysql website (which must be downloaded from the official website to prevent data modification and expires

Backup and restoration of MySQL database in Linux [Root] #/usr/bin/mysqldump-h127.0.0.1-uusername-ppassword databasename>/opt/share/1/backup. SQL /Usr/bin/mysqldump: The program used for execution; -H: Host Name -U: Database User -P: Database

Generally, we will use the memory of the Oracle instance to 80%-60% of the physical memory of the system (4G memory or above uses more than 80%, 2g memory uses 60%-70%)S = pga + sga_max_size = 80% memory)Db_cache_size = 60% sgaShared_pool_size = sga_

Jboss 4.0 is an open-source application server that uses HypersonicDB as its default database. However, developers may also need to use other types of databases except HypersonicDB. In this article, we will see how to configure other databases on

As shown in, the entire data layer consists of three clusters: Group1, Group2, and group3. these three clusters are the results of horizontal data splitting, of course, these three clusters form a DB containing complete data. Each Group includes one

Install Oracle 11G notes in Ubuntu 12.04. 1. First, update the system to the latest version. Sudo apt-get updateSudo apt-get dist-upgrade 2. Install the dependency packageSudo apt-get install alien binutils build-essential cpp-4.4 debhelper g + +-4.4

Many people know that LOGMNR is used to analyze logs, but few use DUMP to analyze logs. This is because the information analyzed by LOGMNR is easy to read and understand. But sometimes we still need to DUMP to analyze the log file, because it

1. Common Database types include SQLServer, MySql, IBM DB2, and Oracle. 2. DBPwAudit database password cracking tool 1) function: Performs brute force password cracking on the target database by attaching a dictionary. Currently, the supported

Oracle RAC normal restart sequence:Oracle 10g rac:Generally, the 10g RAC (ASM) Switch sequence is as follows:1) Stop Oracle RAC 10g environmentStop the Oracle instance first. When this instance (and related services) is closed, the ASM instance is

MySQL two-way replication (master mode) Environment: A: 192.168.1.1 no data B: 192.168.1.2 no data Add the following content to the [mysqld] field of: Auto-increment = 2 (Growth Value) A will grow like Auto-increment-offset = 1 (initial value) Add

Always use MySQL 5.0. After a batch of large data tables have been imported recently, the database has become very slow. The reason is that the performance of the InnoDB engine is severely impaired. Then upgrade the database to MariaDB 10.0.2

Effect of order by sorting on Performance -*********************************** Case Study -*********************************** Alter system flush shared_pool; Set autotrace traceonly explain stat; Select * from t3 where sid> 90; Execution Plan ------

1. Environment Description OS: Linux RedHat5.5 Oracle version: Oracle RAC 11.2.0.1 2. Problem Description Use exp to export data of multiple users in the database. The statement is exp buffer = 4096000 file = exp. dmp wner = user1, user2 .... The

Environment CentOS 6 x86_64, Oracle 11g R2 Solution Oracle provides dbstart and dbshut scripts in the $ ORACLE_HOME/bin directory to start and stop Oracle. The dbstart script starts the specified database instance and Listener. First,