Database Administrator

The Physical Data Model (Physical Data Model) PDM provides the basic elements required for the initial design of the system and the relationship between related elements; the physical design stage of the database must be detailed on the basis of the

Principle of a master-slave ConfigurationMysql Replication is an asynchronous Replication process, from one mysql instance (Master) to another mysql instance (Slave ), the entire replication process between the master and slave is mainly completed

Database start and stop is an extremely important management function and can only be used by users who connect to the database with the administrator privilege. 1. initialize the parameter file and the server parameter file When starting an

Some friends asked what is instance and database. So the Group of Friends said a lot of things that are very theoretical and theoretical. There are a lot of things online. If the questioner can understand them, he will not ask us. Obviously, the

Since the 9i version, there is a new usage for "Update if there is no insert if there is no" and no SQL is executed twice. The merge command can be used to modify or insert data from one table to another. The insert or modify operation depends on

The cache is between applications and physical data sources. It is used to reduce the frequency of applications accessing physical data sources and improve the running performance of applications. Data in the cache is the replication of data in the

Oracle @ linux: ~> Impdp tbs/tbs directory = dmpdir dumpfile = 20151110.dmp Import: Release 11.2.0.1.0-Production on Sat Dec 31 11:36:18 2011 Copyright (c) 1982,200 9, Oracle and/or its affiliates. All rights reserved. Connected to: Oracle Database 1

Record exit and return usage1. exit is used to exit the loop. Oracle code: Declare V_KBP varchar2 (10 ); Begin Loop IF V_KBPIS NULL THEN EXIT; ENDIF; EndLoop; Dbms_output.put_line ('Logout'); End; After exit jumps out of the loop (in

Based on the "Mongodb cluster configuration (sharding with replica set)" cluster (SEE), try to dynamically Add a shard replica set when the Mongodb cluster is running. (1) Start the replica set Node Run the following three batch files to start three

1. Modify records directly in the databaseMysql> use mysqlMysql> update user set password = password ("new_password") where user = "user_name ";Mysql> flush privileges;In fact, this method is to update a database record. Unlike normal update

Recently, the company's project has been completed. It is a maintenance period. It is not very busy. You have no time to learn new things. Today we are going to learn a NOSQL (non-relational) database redis. Redis is a key-value storage system.

Because the database does not perform timely analysis on the table, Oss_User_Beh_Sum_Day_201110 is a large table, which is automatically created on a daily basis. Because the Code does not place the dictionary table in the first place, the Oracle

Symptom description:The following error message is returned when the ASM storage management cannot join the disk:SQL> alter diskgroup disk add disk '/dev/rdsk/c2t500601603022E66Ad13s6 ';Alter diskgroup disk add disk

In some cases, for example, you only want to install some client software to perform basic operations or tests on connecting to the database. To achieve the connection, you need to install the Oracle client. Therefore, oracle provides a dedicated

@ Echo off@ Title Oracle simple data backup tool: StartBackupDataClsEcho.Echo Oracle simple data backup toolEcho.Set nowDate = % date :~ 0, 4% % date :~ 5, 2% % date :~ 8, 2%Set/p oraHost = enter the address of the Oracle server (192.168.0.2 by

To sum up, manual database creation is a basic skill that DBAs must possess. Of course, it is not always usable, but it can be clearly understood by me. What is the directory structure of Oracle? Oracle files, tablespaces, authentication methods,

The following SQL statement does not query any records, even though the database has qualified records. This is an Oracle layer-3 query bug. Select cb. * from mw_app.t_cb cb where cb. obj_id in (Select CBA. channel_id from

Database: GetAllPeopleBornAfter. php [Php] Mysql_connect ("Localhost","Root","Shiguang"); Mysql_select_db ("Student"); $ SQL="SELECT * FROM 'student 'where 'scores'> 90"; $ Result= Mysql_query ($ SQL); // Use the browser While($ Fields=

1. Add clusterware nodes On an existing Node Cluvfy stage-pre nodeadd-n node3 [-fixup [-fixupdir fixup_dir] [-verbose] -- A BUG occurs during installation of 11.2.0.2, and shared disk detection is always unsuccessful. Therefore, check that only

Oracle 10046 is an Oracle internal event. The most common method is to set SQL _trace (alter Session set SQL _trace = true) at the session level, that is, to enable the 10046 debugging event of level 1. After a 10046 event is set, Oracle generates a