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You can call autonomous transactions from within a PL/SQL block. Use the pragmaAUTONOMOUS_TRANSACTION. A pragma is a compiler directive. You can declare thefollowing kinds of PL/SQL blocks to be autonomous:■ Stored procedure or function■ Local procedure or function■ Package■ Type method■ Top-level anonymous blockWhen an autonomous PL/SQL block is entered, the transaction context of the caller issuspended. This operation ensures that SQL operations performed in this block (orother blocks cal

Autonomous transactions are independent transactions that can be called from withinanother transaction. An autonomous transaction lets you leave the context of thecalling transaction, perform some SQL operations, commit or undo those operations,and then return to the calling transaction’s context and continue with that transaction.Once invoked, an autonomous transaction is totally independent of the maintransaction that called it. It does not see any of the uncommitted changes made by themain t

In a distributed database, Oracle must coordinate transaction control over anetwork and maintain data consistency, even if a network or system failureoccurs.A distributed transaction is a transaction that includes one or more statementsthat update data on two or more distinct nodes of a distributed database.A two-phase commit mechanism guarantees that all database servers participatingin a distributed transaction either all commit or all undo the statements in thetransaction. A two-phase commit

In previous releases, you could associate a comment with a transaction by usinga commit comment. However, a comment can be associated with a transaction onlywhen a transaction is being committed.Commit comments are still supported for backward compatibility. However, Oraclestrongly recommends that you use transaction names. Commit comments are ignoredin named transactions.Note: In a future release, commit comments will be deprecated.提交注释在之前版本 Oracle 的中 ，用户可以使用提交注释为事务添加

Name a transaction using the SET TRANSACTION ... NAME statement before you startthe transaction.When you name a transaction, you associate the transaction’s name with its ID.Transaction names do not have to be unique; different transactions can have thesametransaction name at the same time by the same owner. You can use any name thatenables you to distinguish the transaction.怎么命名事务在事务开始之前 , 通过SET TRANSACTION ... NAME命名 , 事务名可以重复.[@more@]

You can name a transaction, using a simple and memorable text string. This nameis a reminder of what the transaction is about. Transaction names replace commitcomments for distributed transactions, with the following advantages:■ It is easier to monitor long-running transactions and to resolve in-doubtdistributed transactions.■ You can view transaction names along with transaction IDs in applications.Forexample, a database administrator can view transaction names in EnterpriseManager when moni

You can declare intermediate markers called savepoints within the context of atransaction. Savepoints divide a long transaction into smaller parts.Using savepoints, you can arbitrarily mark your work at any point within a longtransaction. You then have the option later of rolling back work performedbefore the current point in the transaction but after a declared savepoint within the transaction. For example, you can use savepoints throughout a long complex series of updates,soif you make an erro

摘自myourBSP : blog service provider，博客（托管）服务提供商。意思是公司或者非营利组织为单个人或者其他组织免费或者有偿提供blog服务，blog服务包括空间、 blog程序、blog服务维护等。国内有博客中国、blogcn、blogdriver、blogbus等，国外有blogger、typepad等。为什么会有bsp的产生？首先，确实有一大批人想使用blog服务，而不会自己架设服务器和程序，或者因为各种原因，总之自己不可以做bsp说做的事情，所以需要bsp；而bsp因为可以获得用户所产生的流量，及相应的广告位资源，进而获得相应的收益和投资，所以bsp也原因给这些用户

摘自sparkweaverlilina is a simple but powerful news aggregator written in PHP. No database is needed, RSS/ATOM parsing is done by the excelent MagpieRSS library (it is included, no additional installation needed). It features feed auto-discovery and an easy-to-use interface.lilina是一个小而实用的新闻聚合器，越来越多的朋友喜欢把lilina放到自己的博客上，这样可以在自己的网站上与朋友分享知识的同时也很方便地阅读自己订阅的一些博客。lilina目前是一个独立的应用程序.[@more@]

摘自monn-soft传统的网络服务程序，如：ftp、pop和telnet在本质上都是不安全的，因为它们在网络上用明文传送口令和数据，别有用心的人非常容易就可以截获这些口令和数据。而且，这些服务程序的安全验证方式也是有其弱点的，就是很容易受到“中间人”（man-in-the-middle）这种方式的攻击。所谓 “中间人”的攻击方式，就是“中间人”冒充真正的服务器接收你的传给服务器的数据，然后再冒充你把数据传给真正的服务器。服务器和你之间的数据传送被“中间人”一转手做了手脚之后，就会出现很严重的问题。 SSH的英文全称是Secure SHell。通过使

Rolling back means undoing any changes to data that have been performed by SQLstatements within an uncommitted transaction. Oracle uses undo tablespaces (orrollback segments) to store old values. The redo log contains a record of changes.Oracle lets you roll back an entire uncommitted transaction. Alternatively, you can rollback the trailing portion of an uncommitted transaction to a marker called a savepoint.All types of rollbacks use the same procedures:■ Statement-level rollback (due to stat

Committing a transaction means making permanent the changes performed by theSQL statements within the transaction.Before a transaction that modifies data is committed, the following has occurred:■ Oracle has generated undo information. The undo information contains the olddata values changed by the SQL statements of the transaction.■ Oracle has generated redo log entries in the redo log buffer of the SGA. The redolog record contains the change to the data block and the change to the rollbackbl

A transaction in Oracle begins when the first executable SQL statement is encountered.An executable SQL statement is a SQL statement that generates calls to an instance,including DML and DDL statements.When a transaction begins, Oracle assigns the transaction to an available undotablespace to record the rollback entries for the new transaction.A transaction ends when any of the following occurs:■ A user issues a COMMIT or ROLLBACK statement without a SAVEPOINT clause.■ A user runs a DDL statem

Oracle provides a means for suspending, and later resuming, the execution of largedatabase operations in the event of space allocation failures. This enables anadministrator to take corrective action, instead of the Oracle database server returningan error to the user. After the error condition is corrected, the suspended operationautomatically resumes.A statement runs in a resumable mode only when the client explicitly enablesresumable semantics for the session using the ALTER SESSION statement

If at any time during execution a SQL statement causes an error, all effects of the statement are rolled back. The effect of the rollback is as if that statement had never been run. This operation is a statement-level rollback.Errors discovered during SQL statement execution cause statement-level rollbacks. An example of such an error is attempting to insert a duplicate value in a primary key. Single SQL statements involved in a deadlock (competition for the same data) can also cause a statement

A SQL statement that runs successfully is different from a committed transaction. Executing successfully means that a single statement was: ■ Parsed ■ Found to be a valid SQL construction■ Run without error as an atomic unit. For example, all rows of a multirow update are changed. However, until the transaction that contains the statement is committed, the transaction can be rolled back, and all of the changes of the statement can be undone. A statement, rather than a transaction, runs succes

A transaction is a logical unit of work that contains one or more SQL statements. Atransaction is an atomic unit. The effects of all the SQL statements in a transaction canbe either all committed (applied to the database) or all rolled back (undone from thedatabase).A transaction begins with the first executable SQL statement. A transaction ends whenit is committed or rolled back, either explicitly with a COMMIT or ROLLBACK statementor implicitly when a DDL statement is issued.事务简介1. 包含

SNS:Social Network Sofwaret，社会性网络软件，依据六度理论，以认识朋友的朋友为基础，扩展自己的人脉。并且无限扩张自己的人脉，在需要的时候，可以随时获取一点，得到该人脉的帮助。　　SNS网站，就是依据六度理论建立的网站，帮你运营朋友圈的朋友。　　六度关系理论:美国著名社会心理学家米尔格伦(Stanley Milgram)于20世纪60年代最先提出，在人际脉络中，要结识任何一位陌生的朋友，这中间最多只要通过六个朋友就能达到目的。就是说你想认识一个人，托朋友找朋友找认识他的人，之间不会超过六个人。[@more@]

The lowest-level software connecting the user side to the Oracle side of the programinterface is the communications software, which is provided by the host operatingsystem. DECnet, TCP/IP, LU6.2, and ASYNC are examples. The communicationsoftware can be supplied by Oracle, but it is usually purchased separately from thehardware vendor or a third-party software supplier.操作系统的通信传输软件通信传输软件是用户侧连往Oracle侧最底层的程序接口软件[@more@]

Drivers are pieces of software that transport data, usually across a network. Theyperform operations such as connect, disconnect, signal errors, and test for errors.Drivers are specific to a communications protocol, and there is always a default driver.You can install multiple drivers (such as the asynchronous or DECnet drivers) andselect one as the default driver, but allow an individual user to use other drivers byspecifying the desired driver at the time of connection. Different processes can