Category：Database
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Time：2021-5-12
The interview questions are as follows: Redis persistence mechanism Cache avalanche, cache penetration, cache preheating, cache update, cache degradation and so on What are hot data and cold data What are the differences between Memcache and redis? Why is single threaded redis so fast The data types of redis, the usage scenarios of each data […]
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Time：2021-5-12
preface Following the previous pure front-end simulation of the telegram chat systemAfter that, I decided to add back-end functions. This time, I considered using a more concise interface and a more elegant implementation to refactor the UI interface. The main technology stack is vue2 + mongodb + koa2. The project should have been completed and […]
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Time：2021-5-12
1 Introduction It must be known to all the partners who have participated in the background development interview that MySQL transaction is the knowledge that the major interviewers are never tired of asking, but what level do you know about the transactionACIDLast month, this article will accompany you to go deep into the transactions in […]
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Time：2021-5-11
Focus on “Java back end technology stack” Reply to “interview” for full interview information Distributed storage system, which stores data in multiple independent devices. Traditional network storage system uses centralized storage server to store all data. Storage server becomes the bottleneck of system performance and the focus of reliability and security, which can not meet […]
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Time：2021-5-11
Redis persistence What is persistence All redis data is stored in memory, and the update of data willasynchronousSave the file to disk smoothly. The way of persistence snapshot MySQL Dump Redis RDB journal MySQL binlog Redis AOF RDB What is RDB RDB persistence refers to writing the snapshot of data set in memory to disk […]
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Time：2021-5-11
Backup and file back mechanism of tcapsusdb With the rapid development of e-commerce and office online, enterprises are more and more dependent on information system. Database, as the core of information system, plays an important role. For the database, due to the huge amount of data and very important, every data loss may be a […]
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Time：2021-5-11
Configuration and use of plug in Configure the plugin node in mybatis-config.xml configuration file, such as a custom log plug-in loginterceptor and an open source paging plug-in pageinterceptor <plugins> <plugin interceptor=”com.crx.plugindemo.LogInterceptor”></plugin> <plugin interceptor=”com.github.pagehelper.PageInterceptor”> <property name=”helperDialect” value=”oracle” /> </plugin> </plugins> How plug-ins work With the help of the responsibility chain mode, a series of filters are […]
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Time：2021-5-11
This paper mainly introduces the implementation of TinySQLproj2The specific ideas and implementation of the system File TinySQL / parser / parser. Y: 3806 JoinTable: /* Use %prec to evaluate production TableRef before cross join */ TableRef CrossOpt TableRef %prec tableRefPriority { $$ = &ast.Join{Left: $1.(ast.ResultSetNode), Right: $3.(ast.ResultSetNode), Tp: ast.CrossJoin} } /* Your code here. */ […]
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Time：2021-5-11
More interesting, please pay attention to official account number xhJaver 1、 Index data structure I will definitely ask this question during the interview. Why does MySQL choose B + tree as the index? Instead of selecting other indexes, such as B-tree? hash？ The following disk IO refers to the operation of loading data from the […]
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Time：2021-5-11
If we don’t do what we should do today, we will be delayed no matter how early tomorrow. 1、 Comparison of storage engines Note: the above-mentioned b-tree index does not indicate B-tree and B + tree index, but the definitions of B-tree and B + tree are different. In mysql, there are four types of […]
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Time：2021-5-10
AWR is also a very important function in the tools of performance monitoring and problem investigation provided by Oracle database. AWR is similar to Statpack in that it takes a snapshot of the whole state of the dB at a fixed time, and then takes two specified snapshots to calculate the difference, so as to […]
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Time：2021-5-10
Author: Wang Zhibin, a former PGCE of China, is an official certified lecturer of PostgreSQL and a specially invited gold medal lecturer of Pangu cloud classroom. Pgbouncer has three pool modes: transaction pool, session pool and statement pool Transaction connection pool Database clients rarely execute continuous transactions without interruption. Instead, non database work is usually […]
