Http and Chrome dev tools Http header Host: send to where, dns lookup Referer: linked from where, User-Agent: browser, os Cache-Control: static: can cache non-static: cannot cache Date: timestamp Http request methods GET HEAD POST: post data PUT: store data DELETE TRACE OPTIONS CONNECT status 304: cached content Restful api reasons: - single page application - mobile and other services

[TOC] Purpose of Database Management System (DBMS) is to solve problems caused by file systems Data redundancy and inconsistency: duplicate information, file formats Difficulty in accessing data: new program to carry data Data isolation: files and formats Integrity: constraints are fixed, hard to add or change Atomicity of updates: failures may cause inconsistency. Concurrent access by multiple users Security: permissions Schema: the logical structure of the database

按，本文根据陈驰在tigger kaggle小组中的关于kaggle比赛的微讲座整理的。整理者：Wente Guo(正文部分), EK(QA部分及

Greek letters Reference https://oeis.org/wiki/List_of_LaTeX_mathematical_symbols