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Today's sharing is based on: Test Development: Python + Flask implementation interface receives memory information to further share how to use Python + Flask implementation to receive Disk information. Principle: Call the Shell script through Python to execute the Disk related commands, then process them, and then request the Requests libra ...

Next, let's take a look at the implementation of the invoke() method. public Object invoke(Object obj, Object... args) throws IllegalAccessException, IllegalArgumentException, InvocationTargetException{ if (!override) { if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) { Class<?> caller = R ...

The PreparedStatement interface inherits from the Statement interface PreparedStatement is recommended instead of Statement Advantages of Preparedstatement: Prevents SQL injection Faster execution than Statement Support batch processing configuration file Some values that are frequently dynamically modified are recommended to be pla ...

Compact row overflow: Dynamic row overflow: Under what circumstances will overflow Principle: as long as the sum of one line of records exceeds 8 k，Will overflow. Variable field types include blob,text,varchar Index optimization The main function of index is to find and sort. Index optimization is the most basic optimization me ...

* [StandardScaler and MinMaxScaler How to choose?](about:blank#StandardScaler__MinMaxScaler__210) * [Missing value](about:blank#_226) * * [Missing value filling impute.SimpleImputer](about:blank#_imputeSimpleImputer_244) * [Handling typing features: coding and dummy variables](about:blank#_370) * * [preprocessing.LabelEnco ...

When we learn the basic use of reflection, I will use a SmallPineapple class as a template. First, let's get familiar with the basic composition of this class: properties, constructors and methods public class SmallPineapple { public String name; public int age; private double weight; // Only you know your weight public SmallP ...

Terminate the query in advance (for example, when Limit is used, the query will be terminated immediately after finding a satisfactory number of result sets) Optimized sorting (in the old version, MySQL will use two transfer sorts, that is, first read the row pointer and the fields to be sorted, sort them in memory, and then read the data row ...

This tutorial is for beginners to learn python Less nonsense, let's start the python tutorial Let's use tkinter to build the basic interface of the script Private letter Xiaobian 01 can obtain a large number of Python learning resources import tkinter as tk#[size=3] first import tkinter, and install it into python with pip in advance ( ...

In actual development projects, an exposed interface often faces many requests. Let's explain the concept of idempotence: the impact of any multiple execution is the same as that of one execution. According to this meaning, the final meaning is that the impact on the database can only be one-time and cannot be processed repeatedly. The followin ...

1. In the distributed system environment, a method can only be executed by one thread of one machine at the same time; 2. High availability and high performance acquisition lock and release lock; 3. Reentrant feature; 4. Have lock failure mechanism to prevent deadlock; 5. It has the non blocking lock feature, that is, if the lock is not obt ...