Database Administrator

This article describes several methods to quickly find duplicate records in Oracle databases. As an Oracle database developer, you often need to create indexes for one or several columns of tables to provide direct and fast access to rows. However,

The problems caused by transaction concurrency are the problems that need to be solved by the database. The transaction processing technology is very mature, and the four isolation levels plus a snapshot is a common solution for all databases,

Only scripts are provided here, which is exactly the same as the previous "automatic backup of multiple Oracle instances under Aix 5.3, If you want to add at or crontab, refer to automatic backup of MySQL database under CentOS5.4. # MySQL User

Mysql> select * from test;+ -------- + ------ + --------------- + --------- + ------------------------------- +| P_id | g_id | p_name | p_price | p_desc |+ -------- + ------ + --------------- + --------- + ------------------------------- +| Beef1 | 1

Recently, I have re-installed the Ubuntu 10.10 system and need to re-compile and install Mysql. The source code version is 5.1.34. It's a tough task. I don't know what the 10.10 system has changed, and the software installation is so bad. Here we

The installation of python-mysqldb in CentOS took three hours. The strange problem was that python setup. py build had a lot of garbled characters. If you see a friend on the Internet who has encountered the same problem, post it and share it with

I. Preparations Note: because it is installed on a server that already exists and has been used by multiple parties, you must first confirm whether Mysql has been installed on this Linux server. 1. When groupadd mysql, the system prompts that mysql

Error message: Starting MySQL. Manager of pid-file quit without updating file. [FAILED]Vim install_mysql.shCHOST = "x86_64-pc-linux-gnu"CFLAGS = "-march = nocona-O2-pipe"CXXFLAGS = "$ {CFLAGS }"./Configure \"-- Prefix =/usr/local/mysql "\"--

By default, alert log has only one file. When a certain amount of data is accumulated, it is a little troublesome to view alert. log. You can only use the tail-xxx line for viewing. Therefore, if you can store alert. log by day or put it in a

Last time I sorted out some concepts of DB2 database logs (basic knowledge of DB2 logs (1 ), however, it is difficult to manage and prevent archiving logs in the production environment and prevent log loss in case of disaster, because when the DB2

AIX6.1 install Oracle 11g R2 1. Check the server status before installation(1) view memory size# The/usr/sbin/lsattr-E-l sys0-a realmem command is long. If you forget it, you can use man lsattr.(2) view swap space# Lsps-Page Space Physical Volume

The Flashback Database function is very similar to the incomplete recovery of RMAN. It can roll back the entire Database to a certain time point in the past. This function depends on the Flashback log. Faster and more efficient than RMAN. Therefore,

After upgrading mysql from mysql 5.1 to 5.5 in Linux, it is found that the stored procedure is unavailable. When you create and use a stored procedure, The system prompts "Cannot load from mysql. proc. The table is probably updated upted. I checked

Symptom description: Log on to Oracle11g ERROR: ORA-28002: the password will expirewithin 7 days Alarm information: ERROR: ORA-28002: the password will expire within 7 days Cause analysis: SELECT * FROM dba_profiles s WHERE s. profile =

Oracle substr function usage Obtain the string substr (string, start_position, [length]) with the specified start position and length in the string. Substr (string, truncation start position, truncation length) // return the truncated word; When

Error message: ORA-06531: Reference to uninitialized collection Error SQL code: DeclareTYPE t_student_var is table of VARCHAR2 (100 );V_tbl_name t_student_var;BeginSelect name into v_tbl_name (1) from t_student where gid = 1;Select name into

I always wanted to wait for the BETA version to come out and try again, but I still couldn't resist the temptation. In the afternoon, I finally had time to test it.I. necessary software:1. LUAYou can download it from LUA Official Website:

In the RAC environment where two virtual machines are started, we usually need to shut down the host. In this case, the two virtual machines are usually sleep separately. After several practices, after each restart, there are various problems in the

Oracle 10g r2 installation clusterware ocr specified/dev/raw/raw1 Error The following error is reported:That is to say, the permission is incorrect or the owner is not an oracle/Dev/raw:Total 0Crw-rw ---- 1 oracle oinstall 162, 1 Feb 7 raw1Crw-rw ---

I. Syntax of copying a table: Create table name as (subquery) Example: copy the emp table in scott, the default database installed by El. Create table myemp as (select * from emp ); In this example, the table structure and table content are