#导入pandas import pandas as pd import numpy as np #导入SqlAlchemy from sqlalchemy import create_engine if __name__ == "__main__": #建立数据库引擎 engine = create_engine(‘mysql+pymysql://root:mysql@localhost:3306/mymac‘) #写一条sql sql = ‘select id,name,age,gender from student‘ #建立dataframe df = pd.read_sql_query(sql,engine) # print(df) #按照年龄倒序 正序:ascending=True #翻译为sql select * from student order by asc | desc # df = df.sort_values([‘age‘,‘gender‘],ascending=False) # print(df) #取年龄最小的学生 在尾部取值 #翻译为sql select * from student order by age limit 1 # df = df.sort_values([‘age‘]).tail(1) # print(df) #求整个班的平均年龄 avg_age= df.age.mean() #使用loc方法指定字段 print(df.loc[(df[‘age‘]<avg_age ) & df[‘gender‘]==1]) #获取指定字段 # print(df.loc[df[‘gender‘]==1,[‘id‘,‘name‘]]) #将dataframe写入数据表,表名,数据引擎,索引是否入库 # df.to_sql(‘student_copy‘,engine,index=False) #前提要安装好 openpyxl 安装命令 pip install openpyxl #导入成excel文件 # df.to_excel(‘student.xlsx‘) # print(Student.objects.all())
原文地址:https://www.cnblogs.com/Niuxingyu/p/10482314.html
时间: 2024-10-19 14:52:47