Database Administrator

To connect to MySQL, the connection process communicates with the MySQL database instance. From the perspective of development, Process Communication is essentially a process communication. Common process communication methods include pipelines,

This article details Connection management in the Oracle RAC environment, and introduces what are Connect Time Load Balancing, Runtime Connection Load Balancing, Connect Time Connection Failover, and Runtime Connection Failover, TAF, ONS, FCF, FAN,

In the Oracle world, there are three types of data: undo, redo, and data. Redo is a mechanism generated by "no loss of committed transactions" to serve two types of scenarios: instance recovery and media recovery. Instance recovery objective: to

There are two origins:1) Frequent redo records2) server process generates a small amount of data each time. If the redo log file generated each time requires a large number of highly concurrent SPSS to write the redo log file, there are two problems:

During the previous installation, diskgroup used the external redundancy level. Now we want to change it to the normal redundancy level. However, since diskgroup Redundancy cannot be adjusted once it is created, it can only be rebuilt. The procedure

1. MySQL exports local database data to a local file Mysql-A service_db-h your_host-utest-ptest Mysql> select * from t_apps where created> '2017-07-02 00:00:00 'into outfile/tmp/example .csv 2. MySQL exports remote database data to a local file

Environment:OS: Red Hat Linux As 5DB: 11.2.0.1 Today, we found that the data was written to the table of the master database. After switching logs, we found that the data was not transmitted to the slave database. The following error is reported

In Oracle 11g, use sysdba to connect to ASM.SQL> conn/as sysdbaSQL> alter diskgroup DATA mount;Alter diskgroup DATA mount*ERROR at line 1:ORA-15032: not all alterations saved medORA-15260: permission denied on ASM disk groupORA-15260: permission

MySQL open-source database has multiple important branches: MySQL Cluster, MySQL 5.1, MySQL 5.5, and MySQL 6. 2. each branch has the same MySQL database version: Development version, Alpha version, Beta version, RC version, and GA version. The

After Oracle is installed, there is a default database. In addition to this default database, we can also create our own database. For beginners, you can use the 'database Configuration asmap' Wizard to create a Database to avoid troubles. After

Oracle 11G: Generate PFILE file: create pfile = '/home/oracle/initorcl. ora' from spfile;Modify the value of *. memory_target = 536870912 in PFILE.Then restart the database from the new PFILE file to the NOMOUNT state.SQL> startup nomount pfile =

Hibernate automatically creates a table by configuring true and create , You can automatically create a table and display the statement for inserting data on the console. However, the table creation statement cannot be displayed, this is because

Master Database: my. cnf Server-id = 1 ###### only one server-id is allowed Log-bin = mysql-bin Master-host = 192.168.0.121 Master-user = copy ### authorize remote connection Master-password = 1 Master-port = 3306 Slave Database: my. cnf Server-id =

Wmsys. the function of wm_concat is to merge multiple rows into one row. For example, if A person buys three stocks A, B, and C, we will record three data records normally, now we want to display the stock of this person with a piece of data. This

1.fedora17system and mysql-5.1.58.tar.gz download Linux RedHat fedora17 Gonme System: http://download.fedoraproject.org/pub/fedora/linux/releases/17/Live/i686/Fedora-17-i686-Live-Desktop.iso Download

(1) alas, the system has been installed for a day. Although it is not enough to say that Ubuntu does not toss a few partitions, it is time-consuming and labor-consuming. (2) Let's talk about my notebook partition. Because I mainly develop it in

(1) manually simulate the deletion of onlinelog in inactive state. SQL> select * from v $ log; SQL> alter database open;Alter database open*ERROR at line 1:ORA-03113: end-of-file on communication channel Check the alert file: Errors in

Environment: Source environment: System LINUX-32 Oracle: 10.2.0.4 Target environment: System LINUX-64 ORACLE: 10.2.0.4 Preparations: COPY controlfile and spfile backup set. Full database backup set. Archivelog backup set. I. restore SPFILE Use RMAN

Database instance: Each running Oracle database corresponds to an oracle Instance, also known as a routine. When a database on the database server is started, oracle allocates a memory interval for it, called the system global zone (SGA), and then

The Oracle Database Server encountered an error the other day: SQL * Loader-961: An error occurred while calling/loading table 1.ORA-00607: Internal error occurred while making a change to a data blockORA-00600: internal error code, arguments: