commit or rollback

One. DB file Parallel Write wait eventQuote from the following blog:Http://oradbpedia.com/wiki/Wait_Events_-_db_file_parallel_writeDB file Parallel writeThe db file parallel write wait event belongs to the Oracle database writer (DBWR) process

Overview of LocksI. Why to introduce a lockConcurrent operations on a database by multiple users can lead to inconsistencies in the following data:Missing updatesA, a, two users read the same data and modify it, and one of the user's modifications

1 PrefaceThe database large concurrency operation takes into account the deadlock and lock performance issues. See online most vague (especially update lock), so here is a concise explanation, for the following description of the convenient, here

As the complexity of the system increases, the distributed systems we face are growing. Distributed file system, distributed Message Queuing system, and so on, in some industries, especially the Internet industry widely used. DistributedDatabaseIt

Version 1.MySQLMysql> Selectversion ();+------------+|Version ()|+------------+| 5.5.Panax Notoginseng-Log |+------------+1Rowinch Set(0.00Sec2. Create a test tableMysql> Create TableTest_trans (IDint, name_varchar(Ten)); Query OK,0Rows Affected (0.2

Overview of LocksI. Why to introduce a lockConcurrent operations on a database by multiple users can lead to inconsistencies in the following data:Missing updatesA, a, two users read the same data and modify it, and one of the user's modifications

As I looked at the chapters, I briefly reviewed the acid principle of transactional processing of relational databases, where atomicity and persistence were better understood. Because it was not studied in depth before. I have questions about

Originally intended to write about the transaction control process in the SSIS package, it was found that many of the basic concepts needed to be based on the isolation level of SQL Server transactions and transactions. So it took some time to get a

MySQL redo log structure vs. SQL Server log structureInnoDB storage Engine MySQL Technology insiderF1F2F3F4F5F6F7FSql serverHttp://www.cnblogs.com/CareySon/p/3308926.htmlTransaction-to-database changes are broken down into multiple atomic-level

1 PrefaceThe database large concurrency operation takes into account the deadlock and lock performance issues. See online most vague (especially update lock), so here is a concise explanation, for the following description of the convenient, here

When the Binlog option is turned on, the Execute transaction commit command enters the two-phase commit mode. Two-phase submissions are divided into prepare phases and commit two phases. The process is as follows: There are two important parameters

This article was reproduced from: http://blog.csdn.net/yuanyuanispeak/article/details/527561671 PrefaceThe database large concurrency operation takes into account the deadlock and lock performance issues. See online most vague (especially update

Overview of LocksI. Why to introduce a lockConcurrent operations on a database by multiple users can lead to inconsistencies in the following data:Missing updatesA, a, two users read the same data and modify it, and one of the user's modifications

MySQL transaction processing (the engine of the table must be INNODB/BDB)There are two main types of two methods: the first is recommended1. Using Begin,rollback,commit to achieveBegin a transactionROLLBACK TRANSACTION RollbackCommit TRANSACTION

SQL Server shared lock, exclusive lock, update lock use previous/next 2009-11-08 00:29:17/personal Category: DatabaseView (889)/comment (0)/rating (0/0)Overview of LocksI. Why to introduce a lockConcurrent operations on a database by multiple users

Overview of LocksI. Why to introduce a lockconcurrent operations on a database by multiple users can lead to inconsistencies in the following data:Missing UpdatesA, a, two users read the same data and modify it, and one of the user's modifications

Flashback TipsThe following tips and restrictions apply to using flashback features. Flashback tips–performance For better performance, generate statistics on all tables involved in a Flashback Query DBMS_STATS by using the package, and Ke EP

Temporary tables: Like normal tables, there is a structure, but the management of the data is not the same, the temporary table stores the transaction or the intermediate result set of the session, the data saved in the temporary table is only

At the end of the previous chapter, we left the question that in the model described in the previous chapter, the recovery manager had to perform a log recovery through the entire Undolog scan, which is obviously not necessary because the system

The DB2 tutorial being looked at is: DB2 Programming Tips (1). 1 DB2 Programming 1.1 When you create a stored procedure, you must not use the TAB key CREATE PROCEDURE The create can only use a space, but not to use the tab, otherwise