課程資料網(wǎng)盤鏈接：https://pan.baidu.com/s/1-jOwaXWArtv8h21B0-uWGg 提取碼：wsra
SQL零基礎入門筆記：https://www.mubucm.com/doc/4VC7JuHlj6H
云端數(shù)據(jù)庫安裝文檔：https://share.mubu.com/doc/rBUGcUie8H
Python安裝文檔：https://www.mubucm.com/doc/4DJ8YNSNz4F
https://sqlzoo.net/wiki/window_LAG
image.png
select
recovered 累計治愈人數(shù)
,case when recovered = 1 then 'one' when recovered >1 then 'more' else '0'
end
from covid
where recovered > 0
image.png
