Principles of index creation and design

1. Declaration and use of index 1.1 classification of index MySQL indexes include general index, unique index, full-text index, single column index, multi column index and spatial index. In terms of functional logic, there are four kinds of indexes: ordinary index, unique index, primary key index and full-text index. According to the physical i ...

Posted by micbox on Thu, 10 Mar 2022 17:32:18 +0100

0 basic society on the dynamic planning of editing distance (with C + + source code)

catalogue Question 1: judgment subsequence Question 2: different subsequences Question 3: deletion of two strings Question 4: editing distance Today, we continue to study the algorithm problems of dynamic programming, which are a series of algorithm problems about finding editing distance. Let's make a summary. I'll copy these problems t ...

Posted by social_experiment on Thu, 10 Mar 2022 21:51:02 +0100

ffmpeg multi-threaded simple player-carding of main functions

Mainly the next few functions First is the basic definition of the main function VideoState *is; is = av_mallocz(sizeof(VideoState)); if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_TIMER)) { fprintf(stderr, "Could not initialize SDL - %s\n", SDL_GetError()); exit(1); } is->pictq_mutex = SDL_CreateMutex(); is-&gt ...

Posted by reece_1989 on Thu, 10 Mar 2022 19:27:05 +0100

Follow the compilation principle and the main process to realize "printing 1 + 1 results"

Demo prototype project that follows the compilation principle and main process to print 1 + 1 Results Project introduction Printing 1 + 1 results is so complicated that it is not a dazzling skill, but only for simple display: 1. Lexical analyzer; 2. Parser; 3. Script compiler; 4. There are four processes for compiling executors, because the ...

Posted by Big_Ad on Thu, 10 Mar 2022 20:14:59 +0100

[JAVA refined into immortality] magic chapter -- object oriented ② (inheritance, construction method, rewriting, overloading)

🔎 This is JAVA Chengxian road. Pay attention to my learning JAVA and don't get lost 👍 If it helps you, give the blogger a free praise to show encouragement Welcome 🔎 give the thumbs-up 👍 Comment collection ⭐ ️ This chapter introduces the construction method, inheritance, rewriting, overloading and creation method in detail. The whole arti ...

Posted by bsamson on Thu, 10 Mar 2022 21:04:59 +0100

PG Database Source-SysCache Partial Matching Mechanism

The catcache code is located at src/backend/utils/cache/catcache.c, which contains links and operations to initialize SysCache structures and pointer relationships between data structures. Finding tuples in CatCache There are two ways to find tuples in a CatCache: exactly matching the SearchCatCache and partially matching the SearchCatcac ...

Posted by hanhao on Thu, 10 Mar 2022 19:05:13 +0100