Database Administrator

About MySQL database optimization from the O & M perspective A mature database architecture is not designed with high availability, high scaling, and other features at the beginning. It is gradually improved with the increase in the number of users.

Oracle GoldenGate (OGG) diagnostics This document briefly lists the issues that are frequently seen when using Oracle GoldenGate (OGG) and the diagnostic steps and tools. It describes the key file used to find the cause of failure for the OGG Group.

ORA-28001: the password has expired. (password expired) ORA-28001: the password has expired. (password expired), a new feature of Oracle 11g, default user password only valid for 180 days. 1. plsql logs in as an administrator, and system/admin

Oracle data types, functions and stored procedures, and oracle Data TypesString typeFixed Length: char nchar n indicates Unicode encodingVariable Length: varchar2 nvarchar2Number Type: number (P, S) P: integer digits, S decimal

Mysql exports csv files separated by commas (,) and mysql exports csv files by commas (,). In actual work, CleverCode often needs to export some reports or log data. If you directly create a page, if the number of times is not large, the

Error code: 1054 Unknown column't. createUsrId 'in 'group statement', 1054t. createusrid 1. Error description 1 queries executed, 0 success, 1 errors, 0 warnings query: select count (t. id), t. 'createuserid' from t_acs_ints t where t. id not in

MongoDB Series 3: MongoDB user permission operations After preliminary research on configuration and basic understanding, the following section describes MongoDB's user permission operations. Brief Introduction: Like all other databases, permission

MySQL transaction traps and art, mysql transaction traps In the previous article "MySQL transactions and why cannot I imitate transactions in PHP", the author elaborated on the advantages of transactions and introduced some simple SQL commands to

Solve the problem that PLSQL Developer cannot be used to connect to Oracle DB in Windows x64bit environment, x64bitplsql This article is an original article. For more information, see the source: Http://blog.csdn.net/msdnchina/article/details/46416

How to migrate mysql data files to a new hard disk partition, mysql hard disk partition The system adds a hard disk and mounts the new partition to the/data directory. The mysql data File directory is/var/lib/mysql. 1. Stop the mysql Service

Linux Oracle service starts and stops scripts and starts automatically. After installing Oracle 10g R2 in CentOS 6.3 and restarting it, you will find that Oracle is not started on your own. This is normal because Oracle Installation in Linux does

Database locks and databasesPreface Some time ago, I encountered a lot of problems online and in the project about using the GET_LOCK () function of mysql to obtain the lock. There are two main problems: 1. Two locks cannot be obtained at the same

Installation of Oracle in Virtual Machine use PLSQL Developer Connection tutorial in host machine, oracleplsql To meet the development requirements, install the XP system and Oracle on the VM, and install the Oracle Client and PLSQL Developer on the

How to use SQL server for the first time-writing to a newbie and SQL server to a newbie 1. Put the DATA table given by the instructor in the directory [C: \ Program Files \ Microsoft SQL Server \ MSSQL10_50.MSSQLSERVER \ MSSQL \ DATA. 2. enable

Database optimization tutorial (11) Design a beautiful table and database Optimization4. Design a beautiful table The previous chapter describes how to use indexes to accelerate our query statements. This chapter allows us to go back to the initial

How to install different versions of oracle in windows1. Use set oracle_sid = *** to redirect between oracle instances of different versions. 2. You may not be able to log on to the oracle instance in different oracle_home, and the

Atitit. Mssql SQL server converts mysql and paging SQL ast, atitit. mssqlast Atitit. Mssql SQL server converts mysql and sets up paging SQL ast   1. Major conversions: Function Conversion, paging conversion 1 2. Idea: mssql SQL> ast> mysql 1 3. SQL

Introduction and use of schema-workbench, a schema file generation tool in mondrian, I. Installation 1. Prepare jdk1.5 + 2. Download tool: psw-ce-3.4.1.1 and decompress (address as follows) Schema-workbench Click Open Link3. Copy the corresponding

Oracle Database Import, Oracle Database Import When the system was deployed at the electronic Institute in March October, the export and import of the Oracle database were successful using the exp and imp export database commands, I also published

Alter table table_name enable row movement, altertable_name Row movement is literally interpreted as moving rows. by default, a row in an oracle data block does not move in its lifecycle, that is, its rowid does not change. however, in some