Database Administrator

Practical scripts for Oracle permission management At work, you may be exposed to many environmental problems. For permission problems, you always feel overwhelmed and insufficient. There are too many environments, and you may go wrong when granting

Subtotal for Oracle 1. Sequence 1.1 What is Sequence? Sequence is an object provided by Oracle for generating auto-increment primary keys. This is similar to the identity of SQL server. From a mathematical point of view, it is an arithmetic

Ubuntu 14.04 LTS 64-bit installation of Oracle 11g Oracle does not officially state that it supports Ubuntu installation. Therefore, the environment must be adjusted and prepared before installation can be successful. Ps, I tried multiple times but 1

Oracle cascade operations When you add a foreing key constraint, you can also specify the cascade operation type, which is mainly used to determine how to process the foreign key fields in the subtable When deleting a record in the (on delete)

Truncate usage in Oracle Syntax: truncate table; You can use the truncate Statement (DDL language) to delete all records in a table. The truncate statement is usually much faster to delete data than to delete data. This is because no rollback

MySQL Database SQL statement Optimization MySQL index design principles:The index column is generally a column in the where clause or a column in the join clause.Try not to index columns with a small base, such as gender columns.Use a short index as

Oracle starts/disables scott to unlock login, oraclescott After the oracle database is successfully installed, the following problems occur for the first time,   Here, we only provide three methods: L SQL * plus L OEM Console L Windows Console   1.

Article Title, article title Daquan Oracle 11gR2 Clusterware log location:All clusterware daemon logs are stored in the/log/directory. The directory structure is as follows:Alert. log-check this article for most clusterware problems../Admin:./Agent:

Undo tablespaces increase abnormally due to insufficient space for printing and distribution. Today, my colleague found that an exception occurred to a database server he was responsible for. The symptom was that the UNDOTBS tablespace increased,

Warning. Log sequence in archive filename wrapped to fix length as indicated by % S in LOG_ARCHIVE_F, archivefilename The following warning message was found during the database check recently: Thu Apr 02 10:34:39 2015 Current log# 1 seq# 235103

Enq: DM, resetlogsenq In recent cases, the alter database open resetlogs command in db 10.2.0.5.12 has been waiting, and the alert_sid.log information is: Setting recovery target incarnation to 2   The waiting event obtained from v $ session.

How to backup and restore database in SQL Server, backuprestore /* By Dylan SUN */ If you want to backup and restore one database in SQL Server. Firstly, create a shared folder, and add everyone with read/write right. Secondly, backup your

For details about how to add double quotation marks to the table name and field name during oracle SQL statement query, oraclesql As a beginner in oracle, I believe everyone will encounter this problem, It is clear that navicat created a table

Installation and Use of Redis in Linux, linuxredis1. install and use Redis in Linux Official download: http://redis.io/download can download different versions as needed Download, decompress, and install: $ Wgethttp: // download. redis.

Use of database indexes and database Indexes I found a problem today. The problem is probably like this. I can query the interface information and use the local database locally for access. However, the access speed will be very busy after being

Install mysql In debian and mysql In debian Apt-get install mysql-client mysql-server In the middle, you will need to set the password. After the password is set, mysql will be automatically started. You can use ps-ef | grep mysql to view related

Getting started with mysql enterprise backup, enterprisebackup **************************************** * ********************** -- 1. full backup *************************************** * ******************** # mysqlbackup -- defaults-file

Mongodb3.0 Performance Test Report III. mongodb3.0 performance test Mongodb3.0 Performance Test Report 1 Mongodb3.0 Performance Test Report 2 Test environment: Servers: 6 X86 pcservers Cpu: single 8-core Memory: 64 GB Disk: raid 10 Operating System:

Mysql transaction and mysql Transaction ProcessingIntroduction Mysql supports transaction processing since 4.1, but only databases created using InnoDB/BDB engines Support transaction operations. View the mysql database creation engine type: show

Merge multiple oracle rows into one row and multiple oracle rows and one row In mysql, the keyword group_concat provides similar functions. In oracle, the keyword wm_concat is similar. For example, I have the following query data: However, I want