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

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

spring source code - @ Configuration and @ ComponentScan parsing principle

I believe everyone is familiar with the core refresh method started by the spring container. The invokebeanfactoryprocessors method is a very important method for processing beanFactory, @ Component @Bean and so on. 1 @Configuration 2 @ComponentScan("org.springframework.context.annotation") 3 public class MyComponentScan { 4 @ComponentSca ...

Posted by flientje on Thu, 10 Mar 2022 17:14:06 +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

Learning content Es6

catalogue 1, Incomplete deconstruction 2, Deconstruction assignment of object 3, Operator review and extension 1, Incomplete deconstruction 1. If the variable name is less than the value on the right side of the equal sign and there is no other special treatment, the extra value will be ignored 2. There are more variable names than the v ...

Posted by Sakesaru on Thu, 10 Mar 2022 17:14:30 +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