Programmer Think

1. MySql B + index benefits (1) B + tree query is more efficient. The B + tree uses a two-way linked list to connect all leaf nodes, which makes the interval query more efficient (because all data are in the leaf nodes of the B + tree, you only need to scan the leaf nodes once to scan the database). (2) B + tree query efficiency is more stable ...

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1. Preface 1.1 what is a thread pool? Thread pool is a thread management technology realized by using the idea of pooling technology. It is mainly to reuse threads, conveniently manage threads and tasks, and decouple the creation of threads from the execution of tasks. We can create a thread pool to reuse the created threads to reduce the res ...

Common tools Common tools mainly include JDK's own tools and Arthas. JDK's own tools jps virtual machine process status tool Example of tool commands for viewing virtual machine process status $ jps 15236 Jps 14966 Example1 jstat virtual machine statistics monitoring tool Used to view the heap memory, memory information, class loadin ...

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preface As we all know, establishing socket connection is a very performance consuming thing when we make network connection. Especially in the case of distributed, using thread pool to maintain multiple client connections is a very thread consuming behavior. We have to solve one of the above problems through Netty's network connection technol ...

In the previous part, we briefly analyzed the naming specification in the specification, the timing of variable declaration, the specification of if and braces, the common problems and specifications of packaging classes and basic types, and the null pointer in project development. In this article, we continue to talk about some common details ...

A few days ago, I just published an article "custom annotations! Definitely a sharp weapon for programmers to install B!!", Introduced how to use Spring AOP + custom annotations to improve the elegance of the code. Many readers said it was cool to use after reading it, but someone in the background left a message saying that after co ...

Handwritten sql interview questions 1, Data sheet 2, Simple query 1. Check the list of students with "monkey" in their names 3, Summary analysis 1. Query the number of students who have chosen the course 2. Query the highest and lowest scores of each subject and display them in the following form: course number, highest sc ...

👉 Write in front 👈 The origin of this article is that when I searched the Python interview questions of major websites, I found that some of the interview questions in most articles are too basic (not installed by the author) 🍺 Ha), if you don't believe it, look below. Others are even more powerful. I don't know where to copy. They of ...