Database Administrator

// Title: MySQL character set (my summary) // By dx_andy // Time: 2007.8.27 evening // Test environment: win32 MySQL 5.0.45 // Cause: Garbled MySQL Since the launch of MySQL 4.1, the garbled code problem for Chinese people has also aroused the risk

MySQL supports unidirectional and asynchronous replication. During the replication process, a Linux server acts as the master server, and one or more other servers act as slave servers. The master server writes updates to the binary log file and

Grant, view, and manage user permissions in Oracle in Linux. In Oracle databases, user permissions are divided into two types (here we do not discuss the permissions of dba or role, but only the permissions of common users ), system Privilege System

OS: Windows 2003 Server Oracle9.2.0.1 Symptom: When you compile PL/SQL functions with DEBUG, a crash occurs. The details are as follows: The following is a function: SQL> create or replace function A2 (arg_bh User_Tables.table_name % type)2 return

The company's website has just completed the revision, optimized the database structure, and used the memcache distributed cache to add MySQL. In the first few days, the database service has not been down for a few days. however, the machine is

Our server uses the server version of Ubuntu 8 and uses mysql as the server. However, every time we manage databases, we use SQL statements, which is very troublesome, especially when we add data, if there are ',; and other symbols in the added data,

MySQL also designed a native driver called mysqlnd for PHP6, which is a MySQL database driver using the PHP open source protocol (PHP license) and avoids any possible copyright problems, so PHP developers can use it with confidence. Mysqlnd becomes

MySQL has built the Replication function since version 3.23. We can configure it to master-slave mode or master-master mode. The method is very simple. Here we will record the configuration of the master-master. Here I test mysql 5.1.31. One is

I. Account and system roles are combined to improve account security. An account is a name defined in the database system. It is the basic access control mechanism of the database. When connecting to the Oracle database, you need to enter the user

Take scott. emp as an example. Based on the position (MGR) number, find all information about the position number.Create TYPE first: equivalent to the TYPE of each row of record, which can be understood as scott. emp % rowtype1.CREATE or replace

Test environment: DB: 11.2.0.3, 10.2.0.4 OS: RHEL 4.8 Migrate the stored outline data in Oracle 10 Gb to 11 GB 1. Export the data in the test table [Oracle10g @ rhel4 SQL] $ expdp scott/oracle tables = test1directory = testdumpfile = test1.dmp;

We recommend that you change the undo_retention parameter when installing the Oracle software. We recommend that you change the default value of 900 to 10800 seconds, that is, 3 hours; alter system set undo_retention = 10800 scope = both; A part of

This article describes how to build an Oracle database Server. The OS version is Red Hat Enterprise Linux Server release 4/5. In order to pursue higher performance, stability and economy, more and more companies are migrating their database servers

When a frequent commit/rollback or disk I/O problem occurs and a large number of physical read/write contention occurs, we will often see that the LOG FILE SYNC wait event appears in TOP EVENTS, the metrics for evaluating log file sync wait events

Environment Oracle 11.2.0 + SQL Plus Problem The following error occurs when querying the current Sequence value: SQL> SELECT seq_WGB_Test2.CURRVAL FROM dual; SELECT seq_WGB_Test2.CURRVAL FROM dual *Row 3 has an error: ORA-08002: sequence

Oracle 11g installation references1,Install the dependency -------------- under the root user for Ubuntu12.04 32bitSudo apt-get updateSudo apt-get dist-upgradeSudo apt-get install gcc make binutils libc6 libc6-dev lesstif 2 RPM libmotif3 libstdc ++ 5

Important knowledge points to be mastered in Oracle Learning 1. Basic syntax This is required. select, insert, update, where, and so on. To master this knowledge, you can do some verification and testing work. The target is for O & M or testing. 2

A few days ago, my colleague sent an SQL statement saying that the update operation was very slow. I checked that the data volume was not large. Check the execution plan and find that the execution path is incorrect. Why is the execution path

ERROR: ORA-28002: the password will expire within 7 days In Oracle 11G, the default password expiration time is 180 days. If your database does not have such high security requirements You can change it to unlimited. SQL> set wrap off;SQL> set

The target database host to be imported is 10 Gb, and the source data host is 11 GB. To complete the migration, you need to use the function data pump added by Oracle in 10 Gb, in 11g, the data pump can define the version of the exported file. Now