Database Administrator

PRAGMA EXCEPTION_INIT (DEADLOCK_DETECTED,-60 ); EXCEPTION_INIT refers to the command. We can understand it literally, that is, EXCEPTION initialization. The syntax is also simple. pragma exception (exception_name, error_number ); Everyone has

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,

After installing the OOracle software on the Linux platform, you do not need to use dbca to create a database, but manually create a database. The main purpose is to understand the operations performed during database creation. 1. First set the SID

What is session?Generally speaking, session is a context between the communication end and the communication end ). This context is a piece of memory on the server side: it records the client machine of the connection, the application through, and

To_date () and 24-hour notation and display of mm minutes: 1. When using Oracle's to_date function for date conversion, many Java programmers may use "yyyy-MM-dd HH: mm: ss format is converted as the format, but an error occurs in Oracle: "ORA 01810

In data development applications, data needs to be sorted in most cases. However, in Oracle databases, there is a NULL value ). If some values in a column are empty, if this column is sorted, the rows with null values are sorted at the end, for

Sometimes we need to modify the sid and dbname of the database. In addition to using rman for backup and recovery, we can also manually modify it, mainly through two main processes:1. Modify the Instance name (SID)2. Modify the Database Name (dbname)

1. After successful Oracle Installation, you will be prompted to change the password of the supervisor. If you do not change the default password of the account: Internal/oracle Sys/change_on_install System/manager Scott/tiger Sysman/oem_temp 2

To obtain a data set from Oracle Procedure, the Ref Cursor method is usually used. To obtain this Cursor, there are several ways: 1. dynamic SQL return: In this case, Procedure operations are usually relatively simple. For example, you can use a

This article describesFedora 1464-bitInstallOracle Database 11g Release 2 (11.2) 64-bit. This article is based on2G swap partition and SELinux disabled. The installation should also include the following packages:  Gnome Desktop Environment

// In common applications, we use the date function to_date () in many places ()// But we know little about the date function format, or we will not study it at all.// However, knowing how important the date format is// The following is a specific

Jonathan Gennick has been an OTN member since 2001. Oracle Database 10GEnhanced support for hierarchical or tree-like Data Query Recently, I wrote an article in OTN titled query hierarchy: the best support, which discusses Oracle's support for

Oracle is a large database that can be used to store massive data. There are also various ways to import data sources, some of which are constantly added as the business grows, and some are also imported in batch during business system

Oracle data export and import are often used in work, especially in database backup. Exp and imp usage collection network, or that sentence, "Come out and mix, always have to pay back ". I. Definition The oracle exp/imp command is used to

VIP cannot be started normallyDescription: Our environment is 2 node RAC, and node 1 is down due to physical faults.In this case, I want to start the VIP of Node 1 from node 2 so that the single node is transparent to the user program. [Oracle @

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:

MySQL-5.6.10 and MySQL-5.5.34 for source code compilation and installation on CentOS 6.2 1. Install Mysql5.6.10 1. necessary software:Yum-y install gcc-c ++ autoconf automake bison ncurses-devel libtool-ltdl-devel * cmake makeIi. Compilation and

Oracle 12c has a new feature that can archive data in the database, hide infrequently accessed data from the application, and set it to inactive. Of course, it can also be displayed at the session level. This is achieved through the row archival

We know that MongoDB is a non-relational database, so its query method is very different from the standard Structured Query Language SQL. But no matter how complicated it is, when it passes through the developer's hands, it can only become the

In this article, we will build a most simplified MySQL Cluster system. All the commands in the configuration method are run with the root account. This MySQL Cluster contains a management node, two data nodes, and two SQL nodes. These five nodes are