Distributed ID meets the conditions: Global uniqueness: Duplicate ID numbers cannot appear. Since it is a unique identifier, this is the most basic requirement. Increasing trend: Clustered indexes are used in the MySQL InnoDB engine. Since most RDBMS use B-tree data structures to store index data, when selecting primary keys, we should try to use […]
Tag: selection
el-table dynamically adds column and row data, two methods to achieve on-demand selection
Requirements: When there is too much table data, it is necessary to implement the function of dynamically selecting data. There are two methods to select on demand, which solves the problem of splash screen data jitter when the table is dynamically selected. Note that this added data is originally present in tableData. The operation I […]
[Algorithm Selection] Prefix and Special Topic – Three
Article directory Foreword [Subarray whose sum is K](https://leetcode.cn/problems/subarray-sum-equals-k/description/) Title description Think analysis Code [Subarray sums divisible by K](https://leetcode.cn/problems/subarray-sums-divisible-by-k/) Title description Problem-solving instructions: Algorithm idea: Code [Contiguous array](https://leetcode.cn/problems/contiguous-array/submissions/) Title description Think analysis Code [Matrix area sum](https://leetcode.cn/problems/matrix-block-sum/) Title description Think analysis Code ?Summarize Foreword Meaning: The prefix sum is actually for an array of length n. We […]
Look at index structure selection from the comparison of Hash index, binary tree, B-Tree and B+Tree
Look at index structure selection from the comparison of Hash index, binary tree, B-Tree and B + Tree 1. Hash structure 1.1. About Hash data structure 1.2. Why not choose Hash structure for InnoDB index? 1.3. About InnoDB providing adaptive Hash index (Adaptive Hash Index) 2. Binary search tree 3. Balanced binary tree (AVL tree) […]
MSQL Series (11) Mysql Practice-Inner Join Algorithm Underlying Principle and Driver Table Selection
Mysql practice-Inner Join algorithm driven table selection Previously, we explained the index structure of B + Tree, and MySQL’s storage engines MyISAM and InnoDB. We also explained in detail the selection of the underlying driver table of left Join, and had a preliminary understanding that Inner join is a driver table that MySQL actively selects […]
Web page restriction removal code (oil monkey plug-in) can kill most websites and remove restrictions on copying, cutting, text selection, and right-click menus.
// ==UserScript== // @namespace https://www.github.com/Cat7373/ // @name web page restriction lifted // @name:en Remove web limits // @name:zh Web page restriction lifted // @name:zh-CN Web page restriction lifted // @name:zh-TW Web page restriction lifted // @name:ja ウェブのRegulations are relaxed // @description Kill most websites and remove restrictions on copying, cutting, text selection, and right-click menus. […]
vue2+ant-design-vue a-select component secondary packaging (supports single selection/multiple selection to add all selections/pagination (multiple selections across pages)/custom label)
1. Renderings 2. Parameter configuration 1. Code example <t-antd-select v-model=”selectVlaue” :optionSource=”stepList” @change=”selectChange” /> 2. Configuration parameters (Attributes) inherit a-select Attributes Parameter Description Type Default value v-model Bind value boolean / string / number/Array – mode Set ‘multiple”tags’ multi-selection (display all selection ) String – optionSource Drop-down data source Array – width select width (can set […]
Different types, underlying implementation and application scenario selection of C++ hash tables
The basic content of the article is borrowed from “Code Random Record” and is personally organized for review. Basic idea of hash table Hash tables are used to quickly find whether a target value appears in a set. The basic idea is to use the Hash function to convert the target value into the index […]
8 years of experience – Selection comparison of performance stress testing tools!
This article is dedicated to giving an introduction to the concept and background of performance stress testing, and at the same time, provides a corresponding comparison of some performance stress testing tools on the market, so as to help everyone better implement performance stress testing according to their own needs. Why do we need to […]
K value selection skills of Kmeans algorithm [Elbow Method + Silhouette Score Method]
Article directory 1. Brief description of method 2. Datasets used 3. Code implementation 4. Conclusion 1. Brief description of method In the Kmeans algorithm, the selection of the final number of clusters K is mainly judged by two methods: Elbow Method This is a way of plotting the sum of squares over a range of […]