Database Administrator

I. constraint operations1: Change the constraint name:Alter table TName rename constraint oldname TO newname;2: delete ConstraintsAlter table TName drop constraint cname3: Stop ConstraintsAlter table TName modify constraint cname DISABLE;4:

Password Complexity is an important aspect for IT auditors to check whether a system is secure.IT policies often point out that the password should have a minimum length and contain a mix of uppercase letters, lowercase letters, numbers, and special

Check the Rman backup log in the early morning and find an error. The error is as follows:RMAN-00571: ========================================================RMAN-00569: ========= error message stack follows ============RMAN-00571: ==================

A Linux server needs to start multiple data instances, such as DB1 and DB2. Method:Export Oracle_SID = DB1Sqlplus '/as sysdba' Exit! Export ORACLE_SID = DB2Sqlplus '/as sysdba' Exit! For different listening ports, the method for starting the

Ln-s source dist is used to generate a connection (dist) to the source When modifying mysql, remember: 1: Stop the mysql service first (stop all services first and then modify them) Service mysql stop or stop mysql. server stop under mysql

1. Install MySQL under FreeBSD Tar zxf mysql-5.0.41.tar.tar Cd mysql-5.0.41 . /Configure -- prefix =/home/happyiww/mysql-5.1.18-beta -- with-tcp-port = 7788 -- with-unix-socket-path =/tmp/happyiww. mysql. sock -- with_innodb --

The first upgrade is actually a bank production database, which is under heavy pressure and hard to work and has been prepared for a week. on that day, the Bank gave me five hours of time, which is really insufficient. no way, just stick your head

Solve the Problem of freezing mysql-query-browser After I upgrade my system to Ubuntu 8.04, mysql-query-browser will be frozen after I click the database. After searching for a method on the internet, you need to modify a file in the source code.

The little things found during program tuning today. In Windows, if the key value is default null and ''is inserted, an error occurs. If mysql is running in Linux, the value of 0 in the same table is as follows: The table creation statement is the

An error occurred while opening the database startup Oracle in Linux today: ORA-00600: internal error code, arguments: [keltnfy-ldmInit], [46], [1], [], [], [], [], [], [] Later, I checked the information and figured out that I changed the

A table is one of the most basic objects in an Oracle database. From the ground up, the base object is very important for databases. Whether the design is reasonable is directly related to the database performance. From the Oracle database cainiao

Although MySQL 5.1 has released GA after 5.1.30, it is clear that the development of MySQL 5.0 series has not been stopped officially, A new community stable version 5.0.75 has been released on the MySQL ftp server this morning. This is a bug fix

I believe that many system administrators are doing the same job every day-backing up data. Once the system fails and data recovery is required, the system is powerless. It would be nice to set a fixed time every day for the system to automatically

DBLINK details 1. Create dblink Syntax: CREATE [PUBLIC] database link link Connect to username identified by password USING 'string string' Note: 1) permission: The account used to CREATE a database link must have the system permission of create

Install, deploy, and start MongoDB in CentOS. 1. Download the installation package 32-bit Wget http://fastdl.mongodb.org/linux/mongodb-linux-i686-2.2.3.tgz 64-bit Wget http://fastdl.mongodb.org/linux/mongodb-linux-x86_64-2.2.3.tgz Decompress the

Purpose1. Table scanning before index creation1. Which data blocks are scanned?2. Relationship between data blocks3. Physical read4. Logical read5. Test the differences: full table scan and partial Table Record Scan6. Do I scan data blocks for

Environment: OEL + Oracle 11.2.0.1 Since there is already a database instance in the current environment, this does not affect the creation of a new instance sun Current System instance [Oracle @ DBA2 dbs] $ env | grep ORACLEORACLE_SID = orcl1ORACLE_

Oracle 11g has been installed in your Ubuntu environment. We hereby record the installation process and keep it as a memorandum. Prerequisites: 1. system update sudo Sudo apt-get updateSudo apt-get upgrade 2. packagesudo required for system

Compiler path configuration under Codeblocks: I feel that I can understand the compiler compilation and linking mechanism. I am not sure about it here. To put it simply, you need to add some options when compiling a program using the command line:

Let's talk about what they have in common: they are essentially an exclusive lock on resources, all caused by concurrency (if the database has only one session, it cannot be locked ). Next we will focus on their differences: First, they have