Programmer Group

As you know, the CTP interface of futures is provided by the technology company of the previous period. The source code and examples it provides are written in C + + language, which is not convenient to use. For example, I need a database, a program, a K-line chart, and functions like this. I need to do ...

Simple enough To be honest, to implement transaction management and add an annotation to a method, the method automatically implements transactions, which is simple enough. I can't think of anything simpler. This annotation is @ Transactional, which is so excellent. Declarative transaction management ...

1. MySQL functions Official website: https://dev.mysql.com/doc/refman/5.7/en/func-op-summary-ref.html 1.1. Common Functions -- ==================== Common Functions ============================= -- Mathematical operations SELECT ABS(-8) -- absolute value SELECT CEILING(9.4) -- ceil SELECT FLOOR(9. ...

1. ProxyHandler Processing (Proxy Server) 1. Using proxy IP is a common means of crawling 2. Get the address of the proxy server: www.xicidaili.com www.goubanjia.com 3. Proxies are used to hide real access. Proxies do not allow frequent access to a fixed site, so proxies must be many. 4. Basic usage steps: (1) Set proxy address (2) Create a Pox ...

JDBC development steps 1. Registration driver ---Tell the JVM which database driver to use 2. Get connected ---Use the classes in JDBC to complete the connection to the MySQL database 3. Get statement execution platform ---Get the executor object of the SQL statement through the connection object ...

1, concept Spring Batch is a lightweight batch processing framework suitable for enterprise applications. It is worth noting that unlike other scheduling frameworks, Spring Batch does not provide scheduling functions. 2. Batch process Batch processing can be divided into the following steps: Read data Process data according to business The pr ...

Article directory 1. Understand hash function and hash table 1.1 what is Hash 1.2 why there should be Hash 1.3 for example, chestnuts: 1. To use array storage, you need to create new arrays new int[]{2,5,9,13}, and then write a loop to traverse the search: 2. If the hash function is used for calcul ...

Database transactions A series of database operations with ACID characteristics realized by database, a refers to atomicity, C refers to consistency, I refers to isolation, and D refers to persistence; Atomicity refers to that the operation within a transaction is a whole and cannot be subdivided; ...

springboot+mybatis for data addition and deletion In the previous article about creating springboot projects with idea, let's talk about using mybatis for curd. 1. Database Creation 2. The pom.xml file adds mysql dependencies, etc. <!--mysql rely on--> <dependency> ...

Redis details (7) - cluster Before version 3.0 of redis, high availability (HA) can be achieved through Redis Sentinel. After version 3.0, Redis Cluster was officially launched. Its main purpose is to achieve data sharding, but it can also achieve ha, which is currently recommended by the government. In the Redis Sentinel mode, each node needs ...