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What does the browser do after entering the URL

What does the browser do after entering the URL DNS (domain name system) resolution The process of DNS resolution is to find out which machine has the resources you really need baidu.com In fact, it’s not the real address of Baidu website. The only identification of every computer on the Internet is its IP address, But IP address is not easy to remember. Users need to find other computers on the Internet with a more detailed...

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It's really fragrant. We'll make a redux

From college to nowReactIt’s been more than a year since it was developed. Although it’s still a rookie, it’s not easyreactAbuse me a thousand times, I still wait for her as first love. ReduxIt’s the first state manager I use. I always think it depends onreactYes, it isreact-reduxI’m confused. Understand the official website and access to a lot aboutreduxOnly then did I knowreduxandreactas well...

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[20201231] single instance data buffer states.txt

[20201231] single instance data buffer states.txt –//What is the status of Pi? PI represents past image. It is a unique status of Rac environment and will not appear in single instance database.–//Now that this problem is mentioned, today is to explore an example of data buffer states. 1. Environment:[email protected]> @ ver1PORT_STRING                    VERSION       ...

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Tidb source code reading notes (3) online DDL of tidb

Online DDL is always the pain point in the use of database. Previous work, many data center colleagues make complaints about DDL changes are very headache, but also vomit slot, carefully choose the time point. Even so, in the face of complex application systems and various timing operation and maintenance scripts, DDL operation may still interfere with the normal operation of the business. Tidb’s online DDL is based on Google...

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C # state machine stateless

Recently, I’ve been struggling with some control related software design. When I think of the state machine, it’s very useful to solve the state switching of some control systems. There are many introductions about state machine (finite state automata) on the Internet. Simple understanding is to define a series of States, through a series of events, states can be switched between each other. If we do not use the idea of...

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Promise.resolve () and new promise (r = > R (V))

Promise.resolve The parameters of the method are divided into four cases. Parameter is an instance of promise If the parameter is a promise instance, then Promise.resolve This instance will be returned intact without any modification.This is a special case, which will produce different effects from another new promise (r = > R (V)) The parameter is a thenable object Thenable object refers to the object with then method, such as the...