Big data: sparkSQL
2022找工作是学历、能力和运气的超强结合体，遇到寒冬，大厂不招人，可能很多算法学生都得去找开发，测开
测开的话，你就得学数据库，sql，oracle，尤其sql要学，当然，像很多金融企业、安全机构啥的，他们必须要用oracle数据库
这oracle比sql安全，强大多了，所以你需要学习，最重要的，你要是考网络警察公务员，这玩意你不会就别去报名了，耽误时间！
与此同时，既然要考网警之数据分析应用岗，那必然要考数据挖掘基础知识，今天开始咱们就对数据挖掘方面的东西好生讲讲 最最最重要的就是大数据，什么行测和面试都是小问题，最难最最重要的就是大数据技术相关的知识笔试
Big data: sparkSQL
Learning principles, plus language
This is most needed by enterprises, practical programming
RDD is different, it can handle all structured and unstructured data
The best way to deal with the structure alone is sparkSQL
The goal is to make money
Comparison between sparkSQL and hive
Both are distributed sql computing engines
sparkSQL draws on pandas to play
, so it can handle both sql and python
Pandas is processed by a stand-alone machine
, while sparkSQL can be distributed
.
Focus on sql two-dimensional table structure processing
SQL is called structured data processing language
Of course, sparkSQL is the most suitable
There is a sparkContext inside the sparkSession object
to complete RDD programming
to_DF converts to DataFrame
Summarize
提示：重要经验：
1)
2) Learn oracle well, even if the economy is cold, the whole test offer is definitely not a problem! At the same time, it is also the only way for you to test the public Internet police.
3) When seeking AC in the written test, space complexity may not be considered, but the interview must consider both the optimal time complexity and the optimal space complexity.