Database Administrator

We recommend a very good CentOS 4.4 installation of the Oracle 10g system, which is of great learning value. Here I will mainly explain the application of installing the oracle 10g system, including introduction to the knowledge of installing the

-- Create a tablespace Create tablespace qebcp datafile 'C: \ Oracle \ QebCP \ qebcp. ora' Size 100 m reuse default storage (initial 500 k next 500 k pctincrease 20 ); -- Create a table user Create user qebcp identified by buzhidao default

When developing a database, you may sometimes need to read data of the clob type in the Oracle database. For the purpose of code reuse, I wrote the following stored procedure: Read the data of the clob field in the database. I hope to share with you.

Without AUTHID CURRENT_USER, The definer permission (definer rights) is executed as the definer identity. With AUTHID CURRENT_USER, the caller permission (invoker rights) is executed as the caller identity. Example: 1. Create two users: xxpo and

1 For oracle spm and oraclespmOracle11g new feature SPMIt helps maintain the SQL statement characteristics and only allows execution of execution plans with improved performance.Unlike stored outlines, spm is used to stabilize SQL Performance, while

Xtrabackup migrate an INNODB table, xtrabackupinnodb Mysql database. I want to delete a table. The primary key of this table is used as the foreign key of multiple other tables, InnoDB, and cascade deletion is set. This operation obviously

How to stop biee in the creating domain step1. Error: biee11g creating domain csf entries will not be parsed since the adminserver is unreachablenote manager properties2. Oracle also has related content, mainly for windows2003 and windows2008

Database Design Process Previously, I paid for the IDC. However, the database just copied the original database step by step and did not follow the steps. This. NET version of the data center charges a lot of fees for us. The database design has

Database transaction isolation level The main problems to be solved by database software are the conflict between "data consistency" and "Access concurrency". In theory, we have summarized several uncertainties that need to be solved to ensure data

Dangerous: no security vulnerability scan is performed.Consequence: vulnerabilities in the operating system and network programs are discovered by hackers, and even the database is broken.Remedy: always keep the latest security patches and regularly

When I look at the program, I find that as long as it is a piece of SQL statement, it is basically written like this:Where 1 = 1I checked the reason online: I cannot determine whether there is a statement after where. I need to add 1 = 1. If there

Today, due to work needs, we need to find different record values under a certain field in the database. The very simple problem is too complicated and depressing, the reason is that a command of SQL has been forgotten, and the problem has been

Install: Oracle installation has many tutorials on the Internet, which are explained in detail. I will not go into details here. I only provide two links, which may be helpful: Oracle Installation and simple configuration. free installation of

In the process of using MySQL DATA, sometimes we need a field that is not the primary key and does not repeat it. In this case, we need to use the SQL UNIQUE constraint. The following is an introduction from w3school: The UNIQUE constraint

Select to_char (sysdate, 'yyyy-mm-dd hh24: mi: ss'), to_char (trunc (sysdate), 'yyyy-mm-dd hh24: mi: ss ') from dual t; -- sysdate and trunc (sysdate) are different. sysdate at 00:00:00 of the current day is equal to trunc (sysdate) select trunc

133 export the database elink: dbexport-o/home/ap/dcclink/. shan/194/elink; 132 import the database elink: dpimport-c-ddatadbs-I/home/ap/dcclink/. shan/elinkelink.   The problem is as follows: 1. The type of your terminal is unknownto the

27. Which two statements are true regarding tables? (Choose two .)A. A table name can be of any length.B. A table can have any number of columns.C. A column that has a DEFAULT value cannot store null values.D. A table and a view can have the same

Preface: Oracle is a typical C/S structure. The server provides oracle service instances, which are mainly used for database management, object management and storage, and data Storage, query, database resource monitoring, monitoring, and other

I. Basic Concepts In a database, the two basic operations on a data are write and read. The distribution has two types of lock control: exclusive lock (X lock) and shared lock (S lock ). Exclusive lock (x lock): If transaction T adds X lock to data

Manual database creation is a common situation for DBAs because GUI environments cannot be provided in some cases. In fact, it is very convenient to set relevant parameters or values for manual database creation. This document describes the steps