非常简短的文字,却异常明了的说明了一个数据库管理系统的核心原理,原文来自原文

Its a great question, and deserves a long answer.

Most database servers are built in C, and store data using B-tree type constructs. In the old days there was a product called C-Isam (c library for an indexed sequential access method) which is a low level library to help C programmers write data in B-tree format. So you need to know about btrees and understand what these are.

Most databases store data separate to indexes. Lets assume a record (or row) is 800 bytes long and you write 5 rows of data to a file. If the row contains columns such as first name, last name, address etc. and you want to search for a specific record by last name, you can open the file and sequentially search through each record but this is very slow. Instead you open an index file which just contains the lastname and the position of the record in the data file. Then when you have the position you open the data file, lseek to that position and read the data. Because index data is very small it is much quicker to search through index files. Also as the index files are stored in btrees in it very quick to effectively do a quicksearch (divide and conquer) to find the record you are looking for. 
So you understand for one “table” you will have a data file with the data and one (or many) index files. The first index file could be for lastname, the next could be to search by SS number etc. When the user defines their query to get some data, they decide which index file to search through. If you can find any info on C-ISAM (there used to be an open source version (or cheap commercial) called D-ISAM) you will understand this concept quite well.

Once you have stored data and have index files, using an ISAM type approach allows you to GET a record based on a value, or PUT a new record. However modern database servers all support SQL, so you need an SQL parser that translates the SQL statement into a sequence of related GETs. SQL may join 2 tables so an optimizer is also needed to decide which table to read first (normally based on number of rows in each table and indexes available) and how to relate it to the next table. SQL can INSERT data so you need to parse that into PUT statements but it can also combine multiple INSERTS into transactions so you need a transaction manager to control this, and you will need transaction logs to store wip/completed transactions. 
It is possible you will need some backup/restore commands to backup your data files and index files and maybe also your transaction log files, and if you really want to go for it you could write some replication tools to read your transaction log and replicate the transactions to a backup database on a different server. Note if you want your client programs (for example an SQL UI like phpmyadmin) to reside on separate machine than your database server you will need to write a connection manager that sends the SQL requests over TCP/IP to your server, then authenticate it using some credentials, parse the request, run your GETS and send back the data to the client.

So these database servers can be a lot of work, especially for one person. But you can create simple versions of these tools one at a time. Start with how to store data and indexes, and how to retrieve data using an ISAM type interface. 
There are books out there - look for older books on mysql and msql, look for anything on google re btrees and isam, look for open source C libraries that already do isam. Get a good understanding on file IO on a linux machine using C. Many commercial databases now dont even use the filesystem for their data files because of cacheing issues - they write directly to raw disk. You want to just write to files initially.

I hope this helps a little bit.

[转]How do you build a database?的更多相关文章

  1. How do you build a database?

    在reddit上看到的一篇讲解数据库实现的文章,非常有意思,在这里记录一下. 回答者technical_guy: Its a great question, and deserves a long a ...

  2. 如何写一个数据库How do you build a database?(转载)

    转载自:http://www.reddit.com/r/Database/comments/27u6dy/how_do_you_build_a_database/ciggal8 Its a great ...

  3. Using MSBuild to publish a VS 2012 SSDT .sqlproj database project

    http://blog.danskingdom.com/using-msbuild-to-publish-a-vs-2012-ssdt-sqlproj-database-project-the-sam ...

  4. Laravel API Tutorial: How to Build and Test a RESTful API

    With the rise of mobile development and JavaScript frameworks, using a RESTful API is the best optio ...

  5. Microsoft Azure Tutorial: Build your first movie inventory web app with just a few lines of code

    Editor’s Note: The following is a guest post from Mustafa Mahmutović, a Microsoft Student Partner wh ...

  6. Create schema error (unknown database schema '')

    Andrey Devyatka 4 years ago Permalink Raw Message Hi,Please tell me, can I use the static library in ...

  7. Oracle数据库异机升级

    环境: A机:RHEL5.5 + Oracle 10.2.0.4 B机:RHEL5.5 需求: A机10.2.0.4数据库,在B机升级到11.2.0.4,应用最新PSU补丁程序. 目录: 一. 确认是 ...

  8. plsqldevloper + orcal环境搭建

    移动信息安全的漏洞和逆向原理      程序员11月书讯,评论得书啦      Get IT技能知识库,50个领域一键直达 关闭 PL/SQL Developer安装配置实践 2014-04-23 1 ...

  9. Quartz Scheduler(2.2.1) - Working with JobStores

    About Job Stores JobStores are responsible for keeping track of all the work data you give to the sc ...

随机推荐

  1. Flow中的Switch分析

    A switch statement can complete normally iff at least one of the following is true: (1)The switch bl ...

  2. centos7下搭建JAVA项目运行环境。 JAVA+MYSQL+TOMCAT+NGINX

    环境: centos 7 64位 一.配置mysql 5.71.下载mysql源安装包wget http://dev.mysql.com/get/mysql57-community-release-e ...

  3. NLP Attention

    一.概述 自动摘要可以从很多角度进行分类,例如单文档摘要/多文档摘要.单语言摘要/跨语言摘要等.从技术上说,普遍可以分为三类: i. 抽取式摘要(extractive),直接从原文中抽取一些句子组成摘 ...

  4. 安装scrapy报错 error: Microsoft Visual C++ 14.0 is required. Get it with "Microsoft Visual C++ Build Tools": http://landinghub.visualstudio.com/visual-cpp-build-tools

    报错内容:Microsoft Visual C++ 14.0 is required. Get it with "Microsoft Visual C++ Build Tools" ...

  5. pcap简单使用和简单解释

    数据类型bpf_u_int32实际上就是u_int的一个别名,还有吧bpf_int32实际上就是int的别名.当然这个int是32位的,如果操作系统对int的定义不是4字节,bpf_int32就对应另 ...

  6. [笔记] Python字符串

    1.字符串是以单引号'或双引号"括起来的任意文本 比如'Mifen',"Amd794",'-956-$*'等等.注意:不能单双引号组合,涉及字符串中存在单双引号出现,应用 ...

  7. java 基本理论知识点

    通过JAVAOO 的笔试后,总结了一些理论的知识点. 1.main方法是怎么写的 public static void main(String [] args){}//最习惯的 public stat ...

  8. Python jieba库的使用说明

    1.jieba库基本介绍 (1).jieba库概述 jieba是优秀的中文分词第三方库 - 中文文本需要通过分词获得单个的词语         - jieba是优秀的中文分词第三方库,需要额外安装 - ...

  9. composer如何自动验证并获取gitlab的私有库?

        近期购买了Laravel的nova以后,需要对它的核心代码做一些修改,为方便与团队其他成员分享,以及在nova官方库更新后方便对差异管理.便将nova库挂在自己的gitlab,通过compos ...

  10. Java多线程学习之线程的取消与中断机制

    任务和线程的启动很容易.在大多数情况下我们都会让他们运行直到结束,或是让他们自行停止.但是,有时我们希望提前结束任务或是线程,可能是因为用户请求取消,或是线程在规定时间内没有结束,或是出现了一些问题迫 ...