在pandas中使用Sql进行数据处理的方案

import pandas as pd
import pandasql as ps
current = pd.read_csv("cur.csv")
previous = pd.read_csv("pre.csv")

sql = """
select c.`Unnamed: 0` as name, c.sum as current, p.sum as previous, (c.sum - p.sum) as diff 
from current as c left join previous as p 
on c.`Unnamed: 0` = p.`Unnamed: 0`
order by diff desc
"""
pf = ps.sqldf(sql, locals())
pf