online transaction processing oltp

Label:Transactions are required to meet 4 conditions (ACID): atomicity (autmic), consistency (consistency), isolation (isolation), persistence (durability)Atomicity (autmic): The transaction is in execution, to do "either do it or do it all!" ", which means that the transactional part is not allowed to execute. Even if the transaction can not be completed because of the failure, also eliminate the impact on

Read the code of many friends, including some long time friends, in the processing of the database never use transactions, or some although the use of transaction processing, but did not achieve their expected effect. In fact, it is necessary to do a commercial procedure to deal with the data. Here are some issues to deal with my views on the issue. What is calle

mysql5.x have been released for a long time, but there are many people think that MySQL is not support transaction processing, this has to blame them is ignorant, in fact, as long as your MySQL version support BDB or InnoDB table type, then your MySQL has the ability of transaction processing. In this, but also with th

Transaction processing is one of the most important problems to be solved in enterprise application. Java EE provides complete transaction management capabilities through JTA, including the ability to manage multiple transactional resources. But most applications run on a single transactional resource (a database) that does not require a global

Label:Transaction processing in various management systems have a wide range of applications, such as personnel management system, many synchronous database operations need to use the transaction processing. For example, in the Personnel Management system, you delete a person, you need to delete the basic information of the person, but also to delete the informat

:+ ------------------ + ------- +| Variable_name | value |+ ------------------ + ------- +| Have_bdb | Yes || Have_crypt | Yes || Have_innodb | Yes || Have_isam | Yes || Have_raid | Yes || Have_symlink | Yes || Have_openssl | no || Have_query_cache | Yes |+ ------------------ + ------- +8 rows inSet(0.05 sec)If so, we can create a supportTransactionsTry the processed table. MySQL transaction processing fun

, ret; Htlog (ERROR,"DB down\n"); Closedb (); while(1) {printf ("Connect to DB%dth\n", Try_num); RET= Opendb ('L'); if(ret = =0) {printf ("Connect to DB succ\n"); return 0; } closedb (); Sleep ( -); Try_num++; if(Try_num > the) Break ; } printf ("db not open\n"); return-1 ;}/*Close the database*/intClosedb () {EXEC SQL COMMIT work RELEASE; return 0 ;}/*Transaction Rollback*/intDbsrollback () {EXEC SQL ROLLBACK work; return 0;}/*

, indicating a Special Vertex Output Format: Row Q. Each row has one number to indicate the answer. Input and Output sample Input example #1:Copy 5 6 6 2 3 1 3 2 5 1 3 3 2 2 5 1 1 3 1 1 1 1 4 1 1 2 5 1 4 1 1 4 5 Output sample #1:Copy 3 2 4 3 4 4 Description For 30% of data, n, m, q For another 30% of data, k = 1 For 100% of data, n, m, q Analysis Online operations: add each vertex to the queue, similar to the modified spfa algorithm; At the same t

Cnacel recoveryRecover database until CancelSelect Auto, try to restore the archive log that you can use, and then re-Recover database until CancelThis time the input cancel completes the incomplete recovery, that is to say, recover two times.Such as:sql> recover database until cancel;Auto......sql> recover database until cancel;Cancel;5. Open the database with ALTER DATABASE open ResetlogsDescription1, this method restores the database is consistent incomplete recovery, will lose the current

Label:See a reality There is a bank account form CREATE TABLE Account (ID int primary KEY, Balance float); Now there is a PHP program , to complete the 1 yuan, go to 2 Number on the account PHP $mysqli=NewMysqli ("localhost","Root","hsp123","Test"); if($mysqliconnect_error) {Die ($mysqli-connect_error); } $sql 1="Update account set balance=balance-2 where Id=1"; $sql 2="Update Account2 set balance=balance+2 where id=2"; $b 1= $mysqli->query ($sql 1) or Die ($mysqlierror); $b 2= $mysqli->q

There is a bank account formCREATE TABLE account(ID int primary KEY,balance float);now there is a php program , to complete the number 1 yuan, transfer to number 2 on the accountTransactionsBasic : transactions are used to guarantee data consistency , which consists of a set of related DML statements that either all succeed or fail altogether. such as : online transfer is typical to use transactions to handle, to ensure the consistency of dataNow

Before we saw the data and the preprocessing of the data, where was the data after processing? Put it in a place called "Data Warehouse".Basic concepts of data warehousing: Definition of Data Warehouse-topic-oriented, integrated, time-varying, non-volatile Operational database Systems VS data Warehouses-Why use Data Warehouse analytics data (OLAP vs OLTP) Data Warehouse Architecture-three-t