Programmer Group

Is there a performance difference between utf8? General? Ci and UTF8? Unicode? CI? #1 building I want to know the performance difference between utf8 ﹣ general ﹣ Ci and UTF8 ﹣ Unicode ﹣ Ci, but I didn't find any benchmarks on the Internet, so I decided to create my own. I created a very simple table with 500000 rows: CREATE TABL ...

Environment: 2 VM virtual machines centos7 x86? 64 bit system Configuration environment requirements: I. two virtual machines need to turn off iptables, turn off firewalld, turn off selinux and turn on time synchronization parameters to ensure that the time of the two virtual machines is consistent2. The sshd service of the two virtual machine ...

service You already know what entities and value objects are.As basic building blocks, they should contain the vast majority of business logic for any application.However, there are some scenarios where entity and value objects are not the best solution.Let's take a look at what Eric Evans mentioned in his book Domain Driven Design: A Way to Co ...

Article directory Cycle and concurrent number control Grammatical structure `for loop concurrent deletion of users for uses a space as a separator when reading a row to get parameters, while uses a row as a separator Concurrency control (FD and named pipeline realize concurrency) -FD file handle -Named pipe -Case: FD and na ...

Today, I saw a blog post on the Internet. The title is: insert 10 million pieces of data into mysql database in 4 minutes. I think it's very interesting, so I record it for myself to learn.MySQL version: mysql-5.7.22-winx64 1. Set the capacity of MySQL database tables The default capacity of the database table is 4M. If the stored data exceeds ...

The importance of data backup 1. In the production environment, the safety of data is very important, and any loss of data may have serious consequences 2. Causes of data loss Program error Human error Computer failure Disk failure Disaster and theft Classification of database backup From a physical and logical point of view, backup can be d ...

After the open-source cross platform development framework Weex, Alibaba once again announced another major open-source project AliSQL. The performance of this version is about 70% better than that of community mysql Alibaba mysql git address git address: https://github.com/alibaba/AliSQL.git0. Check whether there is mysql resid ...

With MySQL, I can do similar things: SELECT hobbies FROM peoples_hobbies WHERE person_id = 5; My output: shopping fishing coding But I just want one row and one column: Expected production: shopping, fishing, coding The reason is that I have to select multiple values from multiple tables, and after all joins, I get a lot more ...

I collated Java advanced materials for free, including Java, Redis, MongoDB, MySQL, Zookeeper, Spring Cloud, Dubbo high concurrency distributed and other tutorials, a total of 30G, which needs to be collected by myself.Portal: https://mp.weixin.qq.com/s/JzddfH-7yNudmkjT0IRL8Q   Chatting with friends, he mentioned that the constructor of Reent ...

Preface Paging can be said to be a very common function. Most mainstream databases provide physical paging methods, such as Mysql's limit keyword, Oracle's ROWNUM keyword, etc.; as an ORM framework, Mybatis also provides paging functions. Next, the paging functions of Mybatis are introduced in detail. RowBounds page 1. Introduction to rowb ...