Database Study Notes

Database Study Notes (2)1. Database Security1.1 TCSEC/TDI security level classificationB1 level: "secure" or "trusted" products, truly secure products1.2 Database management system security control modelAccess control process:The database management system authenticates the database users who make SQL access requests to prev ...

Posted by speedyslow on Mon, 02 Jan 2023 10:48:29 +0300

C++ classes and dynamic memory allocation

1. Dynamic memory and classes Static data members are declared in the class declaration and initialized in the file containing the class methods. The scope operator is used during initialization to indicate the class to which the static member belongs. If the static member is an integral or enumeration type const, it can be initialized in the ...

Posted by rocket on Sun, 01 Jan 2023 23:52:07 +0300

Metrics type in Prometheus

From the perspective of storage, all monitoring indicators are the same, but there are some subtle differences in these metric s in different scenarios. For example, the indicator node_load1 in the sample returned by Node Exporter reflects the current system load status, and the sample data returned by this indicator is constantly changing as ...

Posted by mk_silence on Sun, 01 Jan 2023 14:17:59 +0300

The most comprehensive microservice permission control scheme in history

1. Microservice permission design Let me first talk about why I wrote this article, because the actual project needs, we need to control the permissions of each component of our current project page, and then check the commonly used permission frameworks on the Internet, one is shrio, the other is spring security, After reading the comparison, ...

Posted by Travis Estill on Sun, 01 Jan 2023 10:22:23 +0300

Algorithm training camp DAY2_Squaring of ordered arrays, subarrays with the smallest length, spiral matrix II

LeetCode | 977. Squaring an Ordered Array topic: Given an array of integers nums sorted in non-decreasing order, return a new array consisting of the square of each number, also sorted in non-decreasing order. 977. Squaring an Ordered Arrayhttps://leetcode.cn/problems/squares-of-a-sorted-array/ think: When I first thought about the solutio ...

Posted by bloo on Sat, 31 Dec 2022 14:42:36 +0300

Basic operation of cloud computing and big data experiment three HDFS

1. Purpose of the experiment Understand HDFS architecture and working principle Master HDFS deployment environment and steps Master HDFS (cluster startup start-dfs.sh) startup Use Hadoop commands (file addition/deletion/modification/check/upload/download) to operate the distributed file system 2. Experimental content HDFS pseudo-distrib ...

Posted by gaspower on Sat, 31 Dec 2022 06:51:29 +0300

2. FreeRTOS transplantation based on STM32CubeMX - Chapter 2 [FreeRTOS system transplantation]

1. Detailed explanation of STM32cubeMX 1.STM32CubeMX function introduction STM32CubeMX is a powerful piece of software that provides a quick and easy way to develop applications for STM32 microcontrollers. It is designed to increase development efficiency, save time and money, and is used to optimize the performance and reliability of S ...

Posted by QbertsBrother on Sat, 31 Dec 2022 06:07:39 +0300

Still experimental in Vue3 What is Suspense?

Search [Great Move to the World] on WeChat, and I will share with you the front-end industry trends, learning paths, etc. as soon as possible.This article GitHub https://github.com/qq449245884/xiaozhi It has been included, and there are complete test sites, materials and my series of articles for interviews with first-line manufacturers.Suspen ...

Posted by Salkcin on Fri, 30 Dec 2022 10:01:50 +0300

Mathematical Modeling - Interpolation and Fitting

1. Interpolation and fitting 1. What is interpolation and fitting?  Interpolation and fitting is to construct a function through sample data. If the constructed function image is required to pass through all sample points, it is interpolation, otherwise it is fitting. 2. Commonly used one-dimensional interpolation methods (1) piece ...

Posted by russy on Fri, 30 Dec 2022 07:58:35 +0300

Data Analysis: 5 Data Relevance Indicators

1 IntroductionSimilarity measures are important tools in many data analysis and machine learning tasks, allowing us to compare and evaluate the similarity between different pieces of data. There are many different metrics available, each with their own pros and cons, and suitable for different data types and tasks.This article We will explore s ...

Posted by sleepingdanny on Thu, 29 Dec 2022 17:22:17 +0300