pycharm链接数据库的代码

1链接mysql数据库操作

import pymysql

#插入的数据
# id='1'
# user='xiaoming'
# age=20

#链接
db=pymysql.connect(host='localhost',user='root',password='',port=3306,db='spider')
# 游标
cursor=db.cursor()

# 查看版本
# cursor.execute('SELECT VERSION()')
# ata=cursor.fetchone()

#创建库
# cursor.execute("CREATE DATABASE spider DEFAULT CHARACTER SET utf8")

#创建表
# sql='CREATE TABLE IF NOT EXISTS students (id VARCHAR(255) NOT NULL,name varchar(255) NOT NULL ,age INT NOT NULL,PRIMARY KEY (id))'
# cursor.execute(sql)

#插入数据
# sql='INSERT INTO students(id,name,age) values(%s,%s,%s)'
# try:
#     cursor.execute(sql,(id,user,age))
#     db.commit()
# except:
#     db.rollback()

#更新
# set后面的是修改条件，where后面的修改那条数据的查找条件
# sql='UPDATE students SET age = %s WHERE name = %s'
# try:
#     cursor.execute(sql,(25,'xiaoming'))
#     db.commit()
# except:
#     db.rollback()



#删除

# table='students'
# condition='age=20'
# sql='DELETE FROM {} WHERE {}'.format(table,condition)
# try:
#     cursor.execute(sql)
#
#     db.commit()
# except:
#     db.rollback()

#查看
sql='SELECT * FROM students'
try:
    cursor.execute(sql)
    print('count:',cursor.rowcount)
    #查一条
    # one=cursor.fetchone()
    # print('One；',one)
    #查看全部
    resluts=cursor.fetchall()
    print('Result:',resluts)
    print('Result Type',type(resluts))
    for row in resluts:
       print(row)
except:
    print('异常')
db.close()

链接mogon操作

import pymongo
# 链接
client=pymongo.MongoClient(host='localhost',port=27017)
#建库
db=client['text3']
#建表（集合）
collection=db['uu']
#插入数据
# student={
#     'id':'1',
#     'name':'xiaouu',
#     'age':18,
#     'gender':'male'
# }
# result=collection.insert(student)

#查询
#一条
# result=collection.find_one({'age':18})
# print(result)
# 多条
result=collection.find({'age':18})
for i in result:
    print(i)

链接redis

import redis

#链接
#个人推荐
red=redis.Redis(host='localhost',port='6379')
#官方推荐
# re=redis.StrictRedis(host='localhost',port='6379')
#2.通过这个redis链接就可以操作给中命令。
#添加一个字符串
resuslt = red.set('name123','zhangsan123')
# print(resuslt)
resuslt = red.setnx('name123','zhangsan1234')
# print(resuslt)
#添加一个list
list1=['aa','bb','cc','dd','ee','fff','eee']
for l in list1:
    print(red.lpush('list1',l))