m a transactions database

Description in Laravel, to run a group of operations in database transactions, you can use the transaction method in DBfacade. If an exception is thrown in the closure of a transaction, the transaction will be automatically restored. If the closure runs successfully, the transaction is automatically committed. You don'

in A distributed database environment, a database transaction can update data on multiple sites, a database transaction called a distributed transaction. Distribu

Four major features of database transactions: acid (atomic, consistency, isolation, durability)Here, we mainly consider consistency and isolation. To improve the transaction processing efficiency, we usually execute multiple transactions concurrently, which is a very important 'concurrency control' in the

Overview This article summarizes the content of the following three posts: The http://baike.baidu.com/view/2943500.htm's description of update loss is not in place and the instant shared read lock and shared read lock are incorrectly used in solution ". The http://blog.csdn.net/w_l_j/article/details/7354530 did not mention "Update loss" and did not mention it in read uncommitted to ensure that there is no update loss. Translation at the isolation level is more intuitive than traditional translat

the transaction will be updated. However, if an error occurs in any part of the process, for example, an exception occurs when updating the inventory information, or the customer's bank account has insufficient deposits, the transaction will fail. Once a transaction fails, all the information in the database must remain unchanged before the transaction. For example, if the last step fails to update the use

exclusive condition: refers to the process of allocating resources to the exclusive use, that is, for a period of time a resource is occupied by only one process. If there are other processes requesting resources at this time, the requestor can wait until the resource-occupying process is freed. 　　2 ) request and hold condition: means that the process has maintained at least one resource, but

commit): Rollback to Pointaa; 4) Transaction commit: Commit 2, A transaction has the following 4 basic characteristics. atomic (atomicity): The operations contained in a transaction are treated as a logical unit, and the operations in this logical unit are all successful, Or they all fail. consistency (consistency): only legitimate data can

Android study notes (8) -- transactions in the Sqlite database, androidsqlite Transaction is the basic unit of concurrency control. A transaction is a sequence of operations. These operations are either executed or not executed. It is an inseparable unit of work. In a simple

Database transactions must have acid properties, and acid is an abbreviation for atomic (atomicity), consistency (consistency), isolation (isolation), and durability (persistence). Atomicity: The entire database transaction is an indivisible unit of work. The entire transaction succeeds only if all operations in the library are executed successfully, and if any

ACID: Refers to the abbreviation for four basic elements that database transactions perform correctly. Contains: atomicity (atomicity), consistency (consistency), isolation (isolation), persistence (durability). One, database transactions have four features:1, atomicity: That is, from

I have recorded that the mvc framework has integrated database transaction processing. It is easy to enable the transaction, as long as you add the [DbTransaction] annotation (attribute) on the action, for example: [HttpPost, DbTransaction]Public void Create (){} The processing method of this annotation is that the database will automatically roll back as long as any exception occurs in the action.The wojil

. At this time, Party B makes another query when preparing for the final update, if the result is 100 yuan, then B will be very confused. I don't know whether to change the account to 100 or 0.The difference between dirty read and dirty read is that dirty read reads are the dirty data not committed by the previous transaction, and non-repeated reads are the data committed by the previous transaction.5. Type 2 lost updates: this is a special case that

In the afternoon, check the alter log of the slave database, and always report the following warning: the slave database is a logical slave database. Mon Aug 5 16:29:17 2013 Warning: The following transaction makes no progressWarning: in the last 30 seconds for the given message!Warning: Xid =0x0003. 025.0013b492 cscn

What is a database transaction? A transaction is a program execution unit consisting of a series of operation sequences. These operations are either done or not done, and are an inseparable unit of work.Four basic properties of database