从老程序员那里嫖来的python小组件

#验证码管理表
class AuthCode(models.Model):
    name = models.CharField(max_length=10,default=None, null=True, blank=True,verbose_name='姓名')
    phone = models.CharField(max_length=11, unique=True, verbose_name='手机号')
    code = models.CharField(max_length=6,verbose_name='验证码')
    purpose = models.IntegerField(default=0,verbose_name='用途:0->注册验证 1->找回密码 2->其它')
    sendNum = models.IntegerField(default=0,verbose_name='发送次数')
    isCanGet = models.BooleanField(default=0,verbose_name='0->可以获取,1->不可以获取')
    recentlySendTime = models.DateTimeField(auto_now_add=True,verbose_name='最近一次发送时间')
    creation_time = models.DateTimeField(auto_now=True, verbose_name='创建时间')

    class Meta:
        verbose_name = '手机验证码'
        verbose_name_plural = verbose_name

import http.client
import urllib
# 使用互亿无线
host = "106.ihuyi.com"
sms_send_uri = "/webservice/sms.php?method=Submit"

# 查看用户名 登录用户中心->验证码通知短信>产品总览->API接口信息->APIID
account = "你的用户名"
# 查看密码 登录用户中心->验证码通知短信>产品总览->API接口信息->APIKEY
password = "你的密码"


def send_sms(text, mobile):
    text = f"您的验证码是：{text}。请不要把验证码泄露给其他人。"
    params = urllib.parse.urlencode(
        {'account': account, 'password': password, 'content': text, 'mobile': mobile, 'format': 'json'})
    headers = {"Content-type": "application/x-www-form-urlencoded", "Accept": "text/plain"}
    conn = http.client.HTTPConnection(host, port=80, timeout=30)
    conn.request("POST", sms_send_uri, params, headers)
    response = conn.getresponse()
    response_str = response.read()
    conn.close()
    return response_str


if __name__ == '__main__':
    mobile = "手机号"
    text = '123122'

    print(json.loads(send_sms(text, mobile).decode('utf-8')))

import qrcode
import io

def maker_qrcode(url):
    """
    生成二维码
    :param url: 需要生成二维码的url
    :return: 返回图片字节流
    """
    image = qrcode.make(url)  # 创建二维码片

    buffer = io.BytesIO()
    # 将图片内容丢入容器
    image.save(buffer, 'png')
    # 返回容器内的字节
    return buffer.getvalue()

或者
from .settings import BASE_DIR

def create_qrcode(name, url):
    """
    生成机器扫码支付二维码
    :param name: 图片名称
    :param url: 支付路由
    :return:
    """
    img = qrcode.make(url, border=0)  # 创建二维码片
    save_path = BASE_DIR + '/' + name + '.png'
    print(save_path)
    img.save(save_path)
    return img

# coding=utf8
import itchat, time

itchat.auto_login(True)

SINCERE_WISH = u'祝%s新年快乐！'

friendList = itchat.get_friends(update=True)[35:]
count = 0

for  index,friend in enumerate(friendList):
    print(index,friend['DisplayName'],friend['NickName'])
    itchat.send(SINCERE_WISH % (friend['DisplayName']
                                or friend['NickName']), friend['UserName'])
    time.sleep(2)
    print('备注名称',friend['DisplayName'],'昵称',friend['NickName'],'用户名',friend['UserName'])

print("----end----")

"""
# 发送文本
itchat.send('Hello, WeChat!')
# 发送图片
itchat.send_image('my_picture.png')
# 发送视频
itchat.send_video('my_video.mov')
# 发送文件
itchat.send_file('my_file.zip')

"""

# -*- coding=utf-8 -*-
import requests
import itchat
import random
#图灵机器人
#http://www.tuling123.com/member/robot/1380138/center/frame.jhtml?page=0&child=0获取apikey
KEY = '你的KEY'

def get_response(msg):
    apiUrl = 'http://www.tuling123.com/openapi/api'
    data = {
        'key'    : KEY,
        'info'   : msg,
        'userid' : 'wechat-robot',
    }
    try:
        r = requests.post(apiUrl, data=data).json()
        return r.get('text')
    except:
        return

@itchat.msg_register(itchat.content.TEXT)
def tuling_reply(msg):
    defaultReply = 'I received: ' + msg['Text']
    robots=['','','']
    reply = get_response(msg['Text'])+random.choice(robots)
    return reply or defaultReply

itchat.auto_login(enableCmdQR=False)
itchat.run()

import re
t = """
    goods_id = models.IntegerField(verbose_name='商品编号')
    label_code = models.CharField(max_length=20, verbose_name='商品标签')
"""
# 字典
print({k:None for k in re.findall('([a-z_A-Z]+)\s=\s',t)})
# 列表
# print([k for k in re.findall('([a-z_A-Z]+)\s=\s',t)])

输出
{'goods_id': None, 'lable_code': None}

import pymysql

def createData(dataDict,tableName):
    """
    给数据表创建数据
    :param dataDict: 字典
    :param tableName: 表名
    :return:
    """
    #连接数据库
    conn = pymysql.connect(
        host='192.168.0.188', #数据库所在地址URL
        user='root', #用户名
        password='123456', #密码
        database='名称', #数据库名称
        port=3306,  #端口号
        charset='utf8'
    )
    #拿到查询游标
    cursor = conn.cursor()
    clos,value = zip(*dataDict.items())
    sql = "INSERT INTO `%s`(%s) VALUES (%s)" % (tableName,
                                                ','.join(clos),
                                                ','.join(['%s'] * len(value))
                                                )
    print(sql)
    cursor.execute(sql, value)
    conn.commit()
    cursor.close()
    conn.close()
    print('Done')

try:
    pass
except 异常类型 as e:
    pass
finally:
    pass


异常类型
Exception  全部异常
AttributeError 试图访问一个对象没有的属性，比如foo.x，但是foo没有属性x
IOError 输入/输出异常；基本上是无法打开文件
ImportError 无法引入模块或包；基本上是路径问题或名称错误
IndentationError 语法错误（的子类） ；代码没有正确对齐
IndexError 下标索引超出序列边界，比如当x只有三个元素，却试图访问x[5]
KeyError 试图访问字典里不存在的键
KeyboardInterrupt Ctrl+C被按下
NameError 使用一个还未被赋予对象的变量
SyntaxError Python代码非法，代码不能编译(个人认为这是语法错误，写错了）
TypeError 传入对象类型与要求的不符合
UnboundLocalError 试图访问一个还未被设置的局部变量，基本上是由于另有一个同名的全局变量，导致你以为正在访问它
ValueError 传入一个调用者不期望的值，即使值的类型是正确的

import datetime

current_time = str(datetime.datetime.now())[:19]
print(current_time)

输出格式如：2018-10-20 10:01:43
local_time = time.strftime('%Y%m%d%H%M%S', time.localtime(time.time()))
print(local_time)

from random import Random
import time

def random_str(randomlength=8):
    str = ''
    chars = 'AaBbCcDdEeFfGgHhIiJjKkLlMmNnOoPpQqRrSsTtUuVvWwXxYyZz0123456789'
    length = len(chars) - 1
    random = Random()
    for i in range(randomlength):
        str+=chars[random.randint(0, length)]
    return str

def order_num():
    """
    生成付款订单号
    :return:
    """
    local_time = time.strftime('%Y%m%d%H%M%S', time.localtime(time.time()))
    result = local_time + random_str(5)
    return result


print(order_num())

CURRENT_TIMESTAMP

为表添加索引

ALTER table tableName ADD INDEX indexName(columnName)

# page.py

from rest_framework.pagination import PageNumberPagination


class UserPagination(PageNumberPagination):
    """用户分页器"""
    page_size = 10  # 默认的页面数据数量
    page_query_param = 'page'  # 定制取数据页码key
    page_size_query_param = 'page_size'  # 默认取数据页码key
    max_page_size = 15   # 数据每页取值的最大上限



# serializers.py

from rest_framework import serializers

from user.models import UserInfo

class UserSerializers(serializers.ModelSerializer):
    """用户收货地址"""

    class Meta:
        model = UserInfo
	    # 所有字段
        #fields = '__all__'
        fields = ['name', 'code', 'title',  'province', 'city',
                    'quxian', 'address', 'code__gte', 'code__lte']
        # 显示外键
        depth = 2


# views.py
class MachineViews(APIView):
    def get(self, request, *args, **kwargs):
        # 从前端获取出来的过滤参数，解析成字典传进filter()函数中
        # 动态过滤，
        kwargs = {}
        # 表中的字段名
        columns = ['name', 'code', 'title',  'province', 'city',
                    'quxian', 'address', 'code__gte', 'code__lte']
        for k, v in request.query_params.items():
            if k not in columns:
                return Response('参数不对', status=status.HTTP_400_BAD_REQUEST)
			if v:
            	kwargs[k] = v

        users = UserInfo.objects.filter(**kwargs)
        page = UserPagination()
        page_goods_list = page.paginate_queryset(users, self.request, self)
        ser = UserSerializers(page_goods_list, many=True)
        return page.get_paginated_response(ser.data)

nohup /home/project_venv/user/bin/python3 -u /home/user/user_server.py >> /home/user/user.log 2>&1 &   

ALTER TABLE tb_commentPhoto ADD CONSTRAINT FK_comment_phone
FOREIGN KEY tb_goodsComment(id) REFERENCES tb_commentPhoto(comment_id);

import csv
import random
import string


def create_invite_code(random_code_pool=None, length=6, num=10, is_append=False):
    """
    创建随机邀请码,并写入txt文件
    :param: random_code_pool 随机邀请码
    :param: length 邀请码长度
    :param: num 邀请码个数
    :param: is_append True追加,False 覆盖
    :return:
    """
    if not random_code_pool:
        code_pool = string.ascii_uppercase + string.digits
        random_code_pool = []
        for i in range(num):
            s = ''
            for _ in range(length):
                s += random.choice(code_pool)
            if s and s not in random_code_pool:
                random_code_pool.append(s)

    # 写入方法。是追加还是覆盖
    write_method = 'a+' if is_append else 'w'
    # 写入文件
    with open('./invite_code.csv', write_method, newline='') as f:
        writer = csv.writer(f)
        for rowData in random_code_pool:
            # 按行写入
            writer.writerow((rowData,))


def check_invite_code(code):
    """
    查看邀请码是否存在txt文件中，
    若存在就返回True，并在txt文件中删除
    若不存在就返回False
    :param code:
    :return:
    """
    code_pool = []
    with open('./invite_code.csv', 'r', encoding='utf-8',errors='ignore') as f:
        allFileInfo = csv.reader(f)
        for row in allFileInfo:
            code_pool.append(row[0])

    if code in code_pool:
        # 删除查询的code
        code_pool.pop(code_pool.index(code))

        # 重新写入文件
        create_invite_code(code_pool,is_append=False)
        return True
    return False


if __name__ == '__main__':
    # create_invite_code(length=9,num=100)
    print(check_invite_code('WJ4PSTJG2'))

print('获取相对路径', request.get_full_path())
print('获取绝对路径', request.build_absolute_uri())
print(request.build_absolute_uri('?'))
print(request.build_absolute_uri('/')[:-1].strip("/"))
print(request.build_absolute_uri('/').strip("/"))
print(request.build_absolute_uri('/'))
print('----------')
print(request.META['HTTP_HOST'])
print(request.META['PATH_INFO'])
print(request.META['QUERY_STRING'])
iphost = request.META.get('REMOTE_ADDR', '')  # 获取访问来源IP


# 输出如：
获取相对路径 /QRcode/?d=1
获取绝对路径 http://127.0.0.1:8000/QRcode/?d=1
http://127.0.0.1:8000/QRcode/
http://127.0.0.1:8000
http://127.0.0.1:8000
http://127.0.0.1:8000/
----------
127.0.0.1:8000
/QRcode/
d=1

先在项目根目录下创建一个static文件夹
然后在settings.py中设置
STATIC_ROOT = os.path.join(BASE_DIR, 'static')
最后执行下面的命令：
python manage.py collectstatic

[uwsgi]
# 使用nginx连接时 使用
socket=0.0.0.0:2019
# 直接作为web服务器使用
#http=0.0.0.1:8000
# 配置工程目录
chdir=/home/user
# 配置项目的wsgi目录。相对于工程目录
wsgi-file=user/wsgi.py
virtualenv=/home/project_venv/user
#配置进程，线程信息
processes=1
threads=1
enable-threads=True
master=True
pidfile=uwsgi.pid
daemonize=uwsgi.log
#启动uwsgi的用户名和用户组
uid=root
gid=root
#uwsgi自动重启
py-autoreload=1

浏览器缓存

Ctrl+Shift+Del  清除Google浏览器缓存的快捷键

Ctrl+Shift+R  重新加载当前网页而不使用缓存内容

git clone -b dev 地址

update user set name='张三' where id=111
# 删除
DELETE FROM table_name [WHERE Clause]

# 增加字段
alter table 表名 add column 列名 类型;
# 删除字段
alter table 表名 dropcolumn 列名 ;

import os
import re


def remove_specified_format_file(file_dir, format_name):
    """
    删除指定格式的文件
    :param file_dir: 文件根目录
    :param format_name: 格式
    :return:
    """
    for root, dirs, files in os.walk(file_dir):
        # print(root) #当前目录路径
        # print(dirs) #当前路径下所有子目录
        # print(files) #当前路径下所有非目录子文件
        for file in files:
            if re.match(format_name, file):
                print(os.path.join(root, file))
                os.remove(os.path.join(root, file))


remove_specified_format_file(r'D:\学习\LDC\java', r'\._*')

import os


def file_count(file_dir):
    """

    :param file_dir: 文件根目录
    :return:
    """
    count = 0
    for root, dirs, files in os.walk(file_dir):
        # print(root) #当前目录路径
        # print(dirs) #当前路径下所有子目录
        # print(files) #当前路径下所有非目录子文件
        count += len(files)
    return count


print(file_count(r'D:\学习\LDC\java\Java学习\newEstore\estore\js'))

import os

def file_size(file_dir):
    """
    删除指定格式的文件
    :param file_dir: 文件根目录
    :return:
    """
    size = 0
    for root, dirs, files in os.walk(file_dir):
        # print(root) #当前目录路径
        # print(dirs) #当前路径下所有子目录
        # print(files) #当前路径下所有非目录子文件
        for file in files:
            size += os.path.getsize(os.path.join(root, file))
	# M为单位
    return size / 1024 / 1024


file_name = r'D:\学习'
print(file_size(file_name))

# html
$.ajax({
                    url: '请求路由',
                    type: 'GET',
                    dataType: 'JSONP',
                    data:{
                      code: 'yes',
                    },
                    jsonp: 'callback',
                    success: function(res) {
                       var selectData = $.parseJSON(res);
                       alert(selectData);
                    },
                    error: function(err) {

                    }
                })

# views.py
def get(self, request, *args, **kwargs):
        code = request.GET.get('code', '')
        # 跨域请求
        callback = request.GET.get('callback', '')
        return HttpResponse("%s('%s')" % (callback, json.dumps({'code': code})), status=status.HTTP_200_OK)

cors解决跨域

https://www.cnblogs.com/wxiaoyu/p/9578848.html

# 序列化器
class MsgSerializers(serializers.ModelSerializer):
    addtime = serializers.DateTimeField(read_only=True, format="%Y-%m-%d %H:%M:%S")
    hasread = serializers.CharField(source='get_hasread_display')
    msgtype = serializers.CharField(source='get_msgtype_display')
    class Meta:
        model = MallMsg
        # 可以混合使用
        fields = '__all__'  # '__all__' 所有字段
        # 数据库层级控制（序列化链表操作）
        # depth = 1  # 外键层级


#分页器
from rest_framework.pagination import PageNumberPagination


class MyLimitOffsetPagination(PageNumberPagination):

    page_size = 3  # 默认的页面数据数量
    page_query_param = 'page'  # 定制取数据页码key ？
    page_size_query_param = 'page_size'  # 默认取数据页码key &
    max_page_size = 15  # 数据每页取值的最大上限

安装openssl
 pip3 install pyOpenSSL

import OpenSSL
import requests
import urllib3.contrib.pyopenssl

urllib3.contrib.pyopenssl.inject_into_urllib3()

def p12_to_pem(certname, pwd):
    """
    从.p12文件中提取pem
    :param certname:
    :param pwd:
    :return:
    """
    pem_name = certname + ".pem"
    f_pem = open(pem_name, 'wb')
    p12file = certname + ".p12"
    p12 = OpenSSL.crypto.load_pkcs12(open(p12file, 'rb').read(), pwd)
    f_pem.write(OpenSSL.crypto.dump_privatekey(OpenSSL.crypto.FILETYPE_PEM, p12.get_privatekey()))
    f_pem.write(OpenSSL.crypto.dump_certificate(OpenSSL.crypto.FILETYPE_PEM, p12.get_certificate()))
    ca = p12.get_ca_certificates()
    if ca is not None:
        for cert in ca:
            f_pem.write(OpenSSL.crypto.dump_certificate(OpenSSL.crypto.FILETYPE_PEM, cert))
    f_pem.close()
    return pem_name


def post_cert_request(url, data,header, certname, pwd):
    """
    使用证书发起https请求
    :param url:
    :param data:
    :param certname:
    :param pwd:
    :return:
    """
    if (certname != ""):
        cert = p12_to_pem(certname, pwd)
    else:
        cert = None
    r = requests.post(url, header=header, data=data, cert=cert)
    return r

python manage.py createcachetable 缓存表名

在工程文件目录下敲入：
python manage.py shell

再在python交互界面输入：
from django.contrib.auth.models import User
user = User.objects.get(username = '用户名')
user.set_password('密码')
user.save()

select * from user  where ISNULL(code)
update user set code='111',info='微信' where ISNULL(code)

tail -f 日志名  实时监控日志
tail -f 80_v10.log

netstat -na|grep 80  查看端口tcp连接数
netstat -na|grep 80 | wc -l 计算端口tcp连接数

ps -ef|grep python  查看有多少python程序在运行

gunzip 2015.csv.gz   # 解压
unzip 19.zip # 解压zip
wc -l 2015.csv   # 查看行数
apt install lrzsz  # 安装
sz 文件名  # 下载文件

查找文件
find / -name 文件名

匹配执行过的以find为开头的命令
history | grep find

# models.py
# 用户管理
class UserManage(models.Model):
    name = models.CharField(max_length=20, verbose_name='用户名')
    phone = models.CharField(max_length=11, unique=True, verbose_name='手机号')
    code = models.CharField(max_length=11, unique=True, verbose_name='编号')

    user = models.ForeignKey(User, on_delete=models.CASCADE, editable=False, null=True, verbose_name='管理员')

# adminx.py
# 用户列表
class UserAdmin(object):
    list_display = [ 'code', 'phone', 'name',]
    search_fields = ['code', 'phone']
    list_filter = ['code', 'phone']
    list_editable = ['name']  # 数据即时编辑
    readonly_fields = ['code', 'phone', 'name']  # 只读字段，不能编辑
    model_icon = 'fa fa-square'
    model = UserInfo

    def has_delete_permission(self, *args, **kwargs):
    	# 禁止删除
        if args:
            return True
        return False

	def has_add_permission(self,*args,**kwargs):
		# 禁止增加
        return False

    def save_models(self):
    	# 用户级别设置
        self.new_obj.user = self.request.user
        flag = self.org_obj is None and 'create' or 'change'
        if flag == 'create':
        	# 对密码字段进行加密
            self.new_obj.password = encrypt_oracle(self.new_obj.password)
        elif flag == 'change':
            if 'password' in self.change_message():
                self.new_obj.password = encrypt_oracle(self.new_obj.password)
        else:
        	pass
        super().save_models()

xadmin.site.register(UserInfo, UserAdmin)

import datetime
import time

start = str(datetime.datetime.now())[:19]
time.sleep(60)
end = str(datetime.datetime.now())[:19]
print(start,end)
link_start = datetime.datetime.strptime(start, '%Y-%m-%d %H:%M:%S')
link_end = datetime.datetime.strptime(end, '%Y-%m-%d %H:%M:%S')
link_min = round((link_end - link_start).seconds / 60, 2)
print(link_min,'分钟')

from tqdm import tqdm,trange
from time import sleep
text = ""
for char in tqdm(["a", "b", "c", "d"]):
    text = text + char
    sleep(1)


# 方式二
import time


def process_bar(percent, index, total,start_time, start_str='', end_str='', total_length=100):
    # 进度条
    percent_length = int(percent)
    bar = '\r' + start_str + ('\033[1;31;41m \033[0m' * percent_length + '\033[1;37;47m \033[0m' * (
                total_length - percent_length)) + f'  {round(index / total * 100, 2)}%  ' + f' {index}|{end_str}'+ f'   |已进行时间: {round(time.time() - start_time, 2)}秒'

    print(bar, end='', flush=True)


if __name__ == '__main__':
    data_set = [i for i in range(23)]
    i = 0
    start_time = time.time()
    total = len(data_set)
    end_str = '{}'.format(total)
    for data in data_set:
        time.sleep(1)
        i += 1
        process_bar(i * 100 / total, i, total, start_time, start_str='', end_str=end_str, total_length=100)

# 方式三
import sys
import time

d = [i for i in range(100)]
for i in range(len(d)):
    time.sleep(1)
    sys.stdout.write('\r>> Downloading  %.2f%%' % (float(i) / float(len(d)) * 100.0))
sys.stdout.flush()

import pandas as pd
lists = [{'a':1,'b':2},{'a':2,'b':3}]
df = pd.DataFrame(lists)
print(df)
df.to_csv('result2.csv')

Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\.md\ShellNew]
"NullFile"=""
"FileName"="template.md"

import datetime
import redis

redis_client = redis.Redis(
    host='127.0.0.1',
    port=6379,
    db=0,
    password='123456'
)

def redis_set():
    """
    redis设置值定时过期
    :return:
    """
    global redis_client

    redis_client.set('name','ldc')
    now = datetime.datetime.now()
    # 设置‘name’50秒过期
    expire_time = now + datetime.timedelta(hours=0, minutes=0, seconds=50)
    redis_client.expireat('name', expire_time)


if __name__ == '__main__':
    redis_set()

import os


def killport(port):
    command = '''kill -9 $(netstat -nlp | grep :''' + str(port) + ''' | awk '{print $7}' | awk -F"/" '{ print $1 }')'''
    os.system(command)


# 开始执行
if __name__ == '__main__':
    port = 4237
    killport(port)

iftop -n -N -i eth0


nethogs eth0


vim +/字符串 文件

from django.contrib.sessions.models import Session
from django.db.models import Q
from django.utils import timezone
from django.utils.deprecation import MiddlewareMixin


class XadminMiddleware(MiddlewareMixin):
    def process_request(self, request):
        """xadmin后台单点登录"""
        PATH_INFO = request.META.get('PATH_INFO', '')
        if PATH_INFO and 'xadmin' in PATH_INFO:
            request.session.clear_expired()   # 清除过期的key
            session_key = request.session.session_key
            for session in Session.objects.filter(~Q(session_key=session_key), expire_date__gte=timezone.now()):
                data = session.get_decoded()
                if data.get('_auth_user_id', None) == str(request.user.id):
                    session.delete()

urlpatterns = [
...
re_path('^xadmin/', xadmin.site.urls),
...
]

   MIDDLEWARE = [
   ...

   'utils.xadminauth.XadminMiddleware',
   ...
   ]
SESSION_COOKIE_AGE = 1209600  # 设置过期时间
   SESSION_SAVE_EVERY_REQUEST = Ture  # 每次请求都更新

# 导入第三方包
pip install django-crispy-forms==1.7.2

# 在settings.py中添加应用
INSTALLED_APPS = [
...
'drf_multiple_model',
'rest_framework',
...
]

# 在views.py中使用
    from drf_multiple_model.pagination import MultipleModelLimitOffsetPagination
    from drf_multiple_model.views import ObjectMultipleModelAPIView


    class LimitPagination(MultipleModelLimitOffsetPagination):
        # 多个models数据表联合查询，分页，每页限制数据10条
        default_limit = 10

    class StudentSerializers(serializers.ModelSerializer):
        """学生表序列化器"""
        # merchant = MerchantSerializers()

        register_time = serializers.DateTimeField(read_only=True, format="%Y-%m-%d %H:%M:%S")

        class Meta:
            model = Student
            fields = '__all__'
    class ClassesSerializers(serializers.ModelSerializer):
        """班级表序列化器"""
        # merchant = MerchantSerializers()

        add_time = serializers.DateTimeField(read_only=True, format="%Y-%m-%d %H:%M:%S")

        class Meta:
            model = Classes
            fields = '__all__'

    class SchoolSerializers(serializers.ModelSerializer):
        """学校表序列化器"""
        # merchant = MerchantSerializers()

        add_time = serializers.DateTimeField(read_only=True, format="%Y-%m-%d %H:%M:%S")

        class Meta:
            model = School
            fields = '__all__'      


    class StudentInfo(ObjectMultipleModelAPIView):
        # 获取学生信息，班级信息，学校信息

        def get(self, request, *args, **kwargs):
            uid = request.GET.get('uid', '')  # 学生id
            cid = request.GET.get('cid', '')  # 班级id
            sid = request.GET.get('sid', '')  # 学校id

            self.querylist = [
                {'queryset': Student.objects.filter(id=uid).order_by('-id'),
                    'serializer_class':  StudentSerializers, 'label': 'student', },
                {'queryset': Classes.objects.filter(id=cid).order_by('-id'),
                    'serializer_class':  ClassesSerializers, 'label': 'classes', },
                {'queryset': School.objects.filter(id=sid).order_by('-id'),
                    'serializer_class':  SchoolSerializers, 'label': 'school', },
            ]

            return self.list(request, *args, **kwargs)

        pagination_class = LimitPagination

class GoodsPriceSerializers(serializers.ModelSerializer):
    """商品价格表序列化器"""

    class Meta:
        model = GoodsPrice
        fields = ['price']

class GoodsSerializers(serializers.ModelSerializer):
    """商品表序列化器"""

    goods_price = GoodsPriceSerializers(many=True, read_only=True)

    class Meta:
        model = Goods
        fields = ['title','goods_price']
        depth = 2

class Goods(models.Model):
    """商品表"""
    title = models.CharField(max_length=50, verbose_name='商品名称')

    class Meta:
        db_table = 'goods'
        verbose_name = '商品信息表'
        verbose_name_plural = verbose_name

    def __str__(self):
        return self.title

class GoodsPrice(models.Model):
    """商品价格表,通过外键关联商品信息表"""

    price = models.DecimalField(max_digits=10, decimal_places=2, default=0, verbose_name='售价')
    goods = models.ForeignKey(to='Goods', related_name='goods_price', on_delete=models.SET_NULL, blank=True, null=True,verbose_name='商品')

    def __str__(self):
        return str(self.price)

    class Meta:
        managed = True
        db_table = 'goodsPrice'
        verbose_name = '商品售价'
        verbose_name_plural = verbose_name

class Footest(APIView):
 def get(self, request, *args, **kwargs):
     # print(request.META)
     if 'MicroMessenger' in request.META['HTTP_USER_AGENT']:
         return Response(data={'msg': '访问来源是微信'})
     elif 'AlipayClient' in request.META['HTTP_USER_AGENT']:
         return Response(data={'msg': '访问来源是支付宝'})
     else:
         return Response(data={'msg': '访问来源是其他'})

from django.urls import path
from 你的应用名称 import views

app_name = '你的应用名称'

urlpatterns = [
    # 其他路由
    ...
    # 导入物流单号
    path('importkdorderno/', views.ImportKDOrderNo.as_view(), name='importkdorderno'),
]

import platform
PlATFORM = platform.system()
if PlATFORM == "Linux":
    print('linux')
else:
    print('其他')

# 联合更新
update malluser set master_master_id=3 where master_id in (select a.id from (select id from  malluser where id like '15%')a)
# 统计某字段重复数据
SELECT phone, COUNT(*) AS sumCount FROM malluser GROUP BY phone HAVING sumCount > 1;

`get_deleted_objects() takes 3 positional arguments but 5 were given`

//如果登录z=xadmin后台的账号不是【root】的就不能点击更新操作
    var master_name = $('#top-nav').find('strong').text();
        master_name =  master_name.substring(4);
    if(master_name != 'root'){
            $(".grid-item a").each(function(index, element) {
                $(this).attr('href','#');
            });
        }

import xadmin

from machine.models import Machine


class MachineAdmin(object):
    list_display = ['code',]  # 显示的字段

    search_fields = ['code']  # 搜索的字段
    list_filter = ['code', 'is_delete'] # 过滤的字段
    ordering = ('-id',) # 按id降序排序
    list_editable = ['is_delete', ]  # 数据即时编辑
    list_per_page = 30  # 每页显示数据数量
    model_icon = 'fa fa-cog fa-spin'  # 左侧显示的小图标

    def has_delete_permission(self, *args, **kwargs):
        # 删除权限
        if self.request.user.is_superuser:  # 管理员才能增加
            return True
        return False

    def has_add_permission(self, *args, **kwargs):
        if self.request.user.is_superuser:  # 管理员才能增加
            return True
        return False

    def has_change_permission(self, *args, **kwargs):
        if self.request.user.is_superuser: # 管理员才能修改
            return True
        return False

    def queryset(self):
        qs = super(MachineAdmin, self).queryset()
        if self.request.user.is_superuser:  # 管理员可以查看所有
            return qs
        else:
            # 登录用户只能看到自己修改的数据
            return qs.filter(master_id=self.request.user.last_name)


xadmin.site.register(MallMachine, MallMachineAdmin)

#设定虚拟主机配置
    server {
        #侦听80端口
        listen 80;
        listen 443 ssl;
        #定义使用 www.nginx.cn访问
		#ssl on;
        server_name  xxx.xxx.com;
        #定义服务器的默认网站根目录位置
        root /root/项目名称;
		ssl_session_timeout 5m;
        ssl_certificate   /etc/nginx/cert/xxx.pem;
        ssl_certificate_key  /etc/nginx/cert/xxx.key;
        ssl_ciphers ECDHE-RSA-AES128-GCM-SHA256:ECDHE:ECDH:AES:HIGH:!NULL:!aNULL:!MD5:!ADH:!RC4;
        ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
        ssl_prefer_server_ciphers on;
        #设定本虚拟主机的访问日志
        #access_log  logs/nginx.access.log  main;

        #默认请求
        location / {
            #倒入了uwsgi的配置
            include uwsgi_params;
		    client_max_body_size	50m;
            #连接uwsgi的超时时间
           # uwsgi_connect_timeout 30;
 	    #设定了uwsig服务器位置
 	    	uwsgi_pass 127.0.0.1:8002;
        }

        location /static{
      	alias /root/项目名称/static;
        }
	location /media {
	alias /root/项目名称/media;
	}

}

ln -s /etc/nginx/sites-available/test /etc/nginx/sites-enabled/test

django + uwsgi + nginx 日志Listen queue size is greater than the system max net.core.somaxconn (128).

修改系统参数

/proc/sys/net/ipv4/tcp_max_syn_backlog  原来2048    改为8192
/proc/sys/net/core/somaxconn	原来128     改为262144

nginx -s reload

# ------------------------邮箱配置-----------------------------------------
EMAIL_BACKEND = 'django.core.mail.backends.smtp.EmailBackend' #把要发送的邮件显示再控制台上，方便调试
EMAIL_USE_SSL = True
EMAIL_HOST = 'smtp.qq.com'  # 如果是 163 改成 smtp.163.com
EMAIL_PORT = 465
EMAIL_HOST_USER = '邮箱账号' # 帐号
EMAIL_HOST_PASSWORD = '授权码'  # 到邮箱里开通
DEFAULT_FROM_EMAIL = EMAIL_HOST_USER

return password_reset_confirm(request=request, uidb36=uidb36, token=token,
                                      template_name=self.password_reset_confirm_template,
                                      token_generator=self.password_reset_token_generator,
                                      set_password_form=self.password_reset_set_form,
                                      post_reset_redirect=self.get_admin_url('xadmin_password_reset_complete'),
                                      current_app=self.admin_site.name, extra_context=context).dispatch(request=request,
                                                                                                        uidb64=uidb36,token=token)

# 成功后跳转路由,根据自己实际来定
self.success_url = self.request.build_absolute_uri('/') + 'xadmin/'

class MallGoodsAdmin(object):
    """商品管理"""
    list_display = ['id', 'show_photo', 'nickname', 'merchant', 'goods_class', 'label',]
    search_fields = ['nickname']
    list_filter = ['goods_class', 'label',]
    model_icon = 'fa fa-bars'
    list_editable = ['goods_class', ]
    #,重写虚拟环境根目录下\Lib\site-packages\xadmin\views\edit.py中的formfield_for_dbfield
    def formfield_for_dbfield(self, db_field, **kwargs):
        # 对MallGoodsClass这个表项的下拉框选择进行过滤
        # MallGoods中有一个goods_class商品分类外键MallGoodsClass，过滤掉外键MallGoodsClass中
        # master_class为空的值
        if db_field.name == "goods_class":
            kwargs["queryset"] = MallGoodsClass.objects.filter(master_class__isnull=False)
            # 对assigned_recipient这个表项的下拉选择进行过滤
        	return db_field.formfield(**dict(**kwargs))
        return super().formfield_for_dbfield(db_field, **kwargs)

xadmin.site.register(models.MallGoods, MallGoodsAdmin)

form.fields[fields[0]].empty_label = None

@filter_hook
    def get_widgets(self):

        if self.widget_customiz:
            portal_pos = UserSettings.objects.filter(
               key=self.get_portal_key())
            if len(portal_pos):
                portal_pos = portal_pos[0].value
                widgets = []

                if portal_pos:
                    user_widgets = dict([(uw.id, uw) for uw in UserWidget.objects.filter(page_id=self.get_page_id())])
                    for col in portal_pos.split('|'):
                        ws = []
                        for wid in col.split(','):
                            try:
                                widget = user_widgets.get(int(wid))
                                if widget:
                                    ws.append(self.get_widget(widget))
                            except Exception as e:
                                import logging
                                logging.error(e, exc_info=True)
                        widgets.append(ws)

                return widgets

        return self.get_init_widget()

plugins/python/uwsgi_python.h:2:20: fatal error: Python.h: No such file or directory

apt install python3-dev

pip install uwsgi

class MallUserAdmin(object):
    """用户管理"""

    list_display = ['id', 'tp_icon', 'nickname', 'phone', 'level', 'balance', 'province', 'city', 'quxian']  # 显示字段
    search_fields = ['id', 'nickname', 'phone']  # 搜索
    list_filter = ['level', 'province', 'city', 'quxian']  # 过滤器
    # list_filter = ['id', 'level', 'province', 'city', 'quxian']  # 如果加id，xadmin加载回来的数据就会很慢，所以不要在过滤器上使用id
    list_per_page = 30  # 默认每页数量
    model_icon = 'fa fa-users'  # 左侧图标
    ordering = ['-id']  # 排序
    readonly_fields = ['subscribe', 'wx_openid', 'phone']  # 只读字段
    is_addbalance = True   # 加载自定义的插件
    relfield_style = 'fk-ajax'  # 其他表如果外键到用户表就做ajax搜索查询，不一次性加载数据

# 新增导出所选数据
# rows = context['results']  
rows = []
select_across = self.request.GET.get('_select_across', False) == '1'
selected = self.request.GET.get('_selected_actions', '')
if self.request.GET.get('selected', 'off') == 'on':
    if not select_across:
        selected_pk = selected.split(',')
        for i in context['results']:
            if str(i['object'].id) in selected_pk:
                rows.append(i)
    else:
        rows = context['results']
else:
    rows = context['results']

{% load i18n %}
<div class="btn-group export">
    <a id="export-menu" class="dropdown-toggle btn btn-default btn-sm" data-toggle="dropdown" href="#">
        <i class="fa fa-share"></i> {% trans "Export" %} <span class="caret"></span>
    </a>
    <ul class="dropdown-menu" role="menu" aria-labelledby="dLabel">
        {% for et in export_types %}
        <li><a data-toggle="modal" data-target="#export-modal-{{et.type}}"><i class="fa fa-arrow-circle-down">
        </i> {% trans "Export" %} {{et.name}}</a></li>
        {% endfor %}
    </ul>

    {% for et in export_types %}
    <div id="export-modal-{{et.type}}" class="modal fade">
        <div class="modal-dialog">
            <div class="modal-content">
                <form method="get" action="">

                    <div class="modal-header">
                        <button type="button" class="close" data-dismiss="modal" aria-hidden="true">&times;</button>
                        <h4 class="modal-title">{% trans "Export" %} {{et.name}}</h4>
                    </div>
                    <div class="modal-body">
                        {{ form_params|safe }}
                        <input type="hidden" name="export_type" value="{{et.type}}">
                        <!-- 增加 导出所选数据 一栏 -->
                        <input type="hidden" name="_selected_actions" value=""/>
                        <input type="hidden" name="_select_across" value=""/>

                        <label class="checkbox">
                            {% if et.type == "xlsx" %}
                            <input type="checkbox" name="export_xlsx_header" checked="checked" value="on">
                            {% trans "Export with table header." %}
                            {% endif %}
                            {% if et.type == "xls" %}
                            <input type="checkbox" name="export_xls_header" checked="checked" value="on">
                            {% trans "Export with table header." %}
                            {% endif %}
                            {% if et.type == "csv" %}
                            <input type="checkbox" name="export_csv_header" checked="checked" value="on">
                            {% trans "Export with table header." %}
                            {% endif %}
                            {% if et.type == "xml" %}
                            <input type="checkbox" name="export_xml_format" checked="checked" value="on">
                            {% trans "Export with format." %}
                            {% endif %}
                            {% if et.type == "json" %}
                            <input type="checkbox" name="export_json_format" checked="checked" value="on">
                            {% trans "Export with format." %}
                            {% endif %}
                        </label>
                        <label class="checkbox">
                            <input type="checkbox" name="all" value="on"> {% trans "Export all data." %}
                        </label>
                        <!-- 增加 导出所选数据 一栏 -->
                        <label class="checkbox">
                            <input type="checkbox" name="selected" value="on"> 导出勾选数据
                        </label>

                    </div>
                    <div class="modal-footer">
                        <button type="button" class="btn btn-default" data-dismiss="modal">{% trans "Close" %}</button>

                        <button class="btn btn-success myexport  glyphicon glyphicon-export " type="submit"><i
                                class="fa fa-share"></i> {% trans "Export" %}
                        </button>
                    </div>
                </form>
            </div><!-- /.modal-content -->
        </div><!-- /.modal-dalog -->
    </div><!-- /.modal -->
    {% endfor %}

</div>

<script type="text/javascript">
    // 如果是订单导出，把待出货订单设置成待收货订单
    $(document).ready(function () {
        $('.myexport').click(function () {
            // 当把订单导出时，需要修改订单状态为待收货状态
            var url = window.location.protocol + '//' + window.location.host + "/exportorder/";
            $("input[name='_select_across']").val($("input[name='select_across']").val());
            if ($("input[name='selected']").is(':checked')) {
                var arr = [];
                $.each($('.action-select'), function () {
                    if (true == $(this).prop('checked')) {
                        arr.push($(this).val());
                    }
                });
                if(arr.length == 0){
                    alert('请先勾选导出数据')
                    return false
                }
            }else{
                var arr = []
                var order_type = $('.breadcrumb li').eq(1).text().trim()
                $('.grid-item').each(function (index, el) {

                    arr.push($(el).find('td').eq(1).text().trim())
                })
            }
            if (($('.breadcrumb > li').eq(1).text()).indexOf('订单') != -1) {
                // 5秒后执行
                setTimeout(function () {
                    $.ajax({
                        type: "POST",
                        url: url,
                        data: {'orderlist': JSON.stringify(arr), 'order_type': order_type,},
                        beforeSend: function (xhr) {
                            xhr.setRequestHeader("X-CSRFToken", $.getCookie("csrftoken"))
                        },
                        success: function (data) {
                            window.location.reload();
                        },
                        error: function (xhr) {
                            alert("出现未知错误");
                            window.location.reload();
                        }
                    });
                }, 5000);
            }
        });
    })
</script>

from django.db.models import F
# 使用F查询更新用户余额
balance = 5  
MallUser.objects.filter(id=1).update(balance=F('balance') + balance)

update Malluser set balance=balance + 5 where id=1;

import logging
import platform
# 全局函数
PlATFORM = platform.system()
if (PlATFORM == "Linux"):
    # linux系统,文件保存在var下
    SERVER_LOG_PATH = '/var/mylog.log'
else:
    # windows系统,文件保存在D盘下
    SERVER_LOG_PATH = 'D:\mylog.log'
# 定义一个logging的对象，命名为mylog
LOGGER = logging.getLogger('mylog')
# 设置级别为WARNING
LOGGER.setLevel(logging.WARNING)
# 创建一个handler，用于写入日志文件
fh = logging.FileHandler(SERVER_LOG_PATH, encoding='utf-8')
fh.setLevel(logging.WARNING)
# 定义handler的输出格式
formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s', datefmt='%Y-%m-%d %H:%M:%S')
fh.setFormatter(formatter)
# 给Logger添加handler
LOGGER.addHandler(fh)
# 不在控制台显示
LOGGER.propagate = False

score = {'小明': {'avg_score': 90, 'English': 90, 'Math': 90, 'Chniese': 90, },
     '小红': {'avg_score': 60, 'English': 60, 'Math': 61, 'Chniese': 59, },
     '小黑': {'avg_score': 70, 'English': 75, 'Math': 65, 'Chniese': 70, },
     '小白': {'avg_score': 80, 'English': 95, 'Math': 65, 'Chniese': 80, },
     }
# 对姓名进行排序，即对键名进行排序
b = sorted(score.items(), key=lambda x: x[0], reverse=True)
show_str = ''
for info in b:
    # print(info)
    key, value = info[0], info[1]
    show_str += '姓名：{},平均分：{}，成绩：{}'.format(key,value['avg_score'], value) + '\r\n'
print('对姓名进行排序')
print(show_str)
# 对平均分进行排序
b = sorted(score.items(), key=lambda x: x[1]['avg_score'], reverse=True)
show_str = ''
for info in b:
    # print(info)
    key, value = info[0], info[1]
    show_str += '姓名：{},平均分：{}，成绩：{}'.format(key,value['avg_score'], value) + '\r\n'
print('对平均分进行排序')
print(show_str)

# 对英语成绩进行排序
b = sorted(score.items(), key=lambda x: x[1]['English'], reverse=True)
show_str = ''
for info in b:
    # print(info)
    key, value = info[0], info[1]
    show_str += '姓名：{},平均分：{}，成绩：{}'.format(key,value['avg_score'], value) + '\r\n'
print('对英语成绩进行排序')
print(show_str)

对姓名进行排序
姓名：小黑,平均分：70，成绩：{'avg_score': 70, 'English': 75, 'Math': 65, 'Chniese': 70}
姓名：小红,平均分：60，成绩：{'avg_score': 60, 'English': 60, 'Math': 61, 'Chniese': 59}
姓名：小白,平均分：80，成绩：{'avg_score': 80, 'English': 95, 'Math': 65, 'Chniese': 80}
姓名：小明,平均分：90，成绩：{'avg_score': 90, 'English': 90, 'Math': 90, 'Chniese': 90}

对平均分进行排序
姓名：小明,平均分：90，成绩：{'avg_score': 90, 'English': 90, 'Math': 90, 'Chniese': 90}
姓名：小白,平均分：80，成绩：{'avg_score': 80, 'English': 95, 'Math': 65, 'Chniese': 80}
姓名：小黑,平均分：70，成绩：{'avg_score': 70, 'English': 75, 'Math': 65, 'Chniese': 70}
姓名：小红,平均分：60，成绩：{'avg_score': 60, 'English': 60, 'Math': 61, 'Chniese': 59}

对英语成绩进行排序
姓名：小白,平均分：80，成绩：{'avg_score': 80, 'English': 95, 'Math': 65, 'Chniese': 80}
姓名：小明,平均分：90，成绩：{'avg_score': 90, 'English': 90, 'Math': 90, 'Chniese': 90}
姓名：小黑,平均分：70，成绩：{'avg_score': 70, 'English': 75, 'Math': 65, 'Chniese': 70}
姓名：小红,平均分：60，成绩：{'avg_score': 60, 'English': 60, 'Math': 61, 'Chniese': 59}

from operator import itemgetter
data = [
    {'code': 1, 'position': 300, 'time': '1620442242'},
    {'code': 2, 'position': 255, 'time': '1620442242'},
    {'code': 3, 'position': 256, 'time': '1620442242'},
    {'code': 1, 'position': 500, 'time': '1620442242'},
    {'code': 5, 'position': 455, 'time': '1620442242'},
    {'code': 1, 'position': 322, 'time': '1620442242'},
    {'code': 6, 'position': 676, 'time': '1620442242'},
]
data = sorted(data, key=itemgetter('code', 'position'))

print(data)

[
{'code': 1, 'position': 300, 'time': '1620442242'},
{'code': 1, 'position': 322, 'time': '1620442242'},
{'code': 1, 'position': 500, 'time': '1620442242'},
{'code': 2, 'position': 255, 'time': '1620442242'},
{'code': 3, 'position': 256, 'time': '1620442242'},
{'code': 5, 'position': 455, 'time': '1620442242'},
{'code': 6, 'position': 676, 'time': '1620442242'}]

import datetime

# 当前时间转字符串
now = datetime.datetime.strftime(datetime.datetime.now(), '%Y-%m-%d %H:%M:%S')
# 字符串转时间格式
now = datetime.datetime.strptime(now, '%Y-%m-%d %H:%M:%S')
a = now + datetime.timedelta(minutes=-15)
# 时间比较大小
if a < now:
    print('yes')

str_data = '\\u7528\\u6237 ID \\u6216\\u5bc6\\u7801\\u9519\\u8bef'
# 字符串.encode('utf-8').decode('unicode_escape')
str_data_to_zh = str_data.encode('utf-8').decode('unicode_escape')
print(str_data_to_zh)

# 输出
用户 ID 或密码错误

python manage.py makemigrations --empty 你的app名称

apt install lrzsz
sz 123.txt

git log --author="ldc"

pip install  translate

from translate import Translator

name = 'giant panda, panda, panda bear, coon bear, Ailuropoda melanoleuca'
translator = Translator(to_lang="chinese")
translation = translator.translate(name)
print(translation)

translator= Translator(from_lang="chinese",to_lang="english")
translation = translator.translate("我想你")
print(translation)


输出：

大熊猫，熊猫，熊猫熊，浣熊，大熊猫
I missed you.

import ast
import json

target_str = '{"h": 1, "e": 2, "l": 3, "l": 4, "o": 5}'
target_str2 = "{'h': 1, 'e': 2, 'l': 3, 'l': 4, 'o': 5}"

# 方式1：使用json，缺点，字符串中不能出现单引号
# 由于 json 语法规定 数组或对象之中的字符串必须使用双引号，不能使用单引号
# 官网https://www.json.org/json-en.html上有一段描述是
# A string is a sequence of zero or more Unicode characters, wrapped in double quotes, using backslash escapes
print(json.loads(target_str))
# print(json.loads(target_str2))   # 使用json转这个字符串会报错 Expecting property name enclosed in double quotes

# 方式2：使用eval函数，缺点，不安全
print(eval(target_str))
print(eval(target_str2))
# print(eval("__import__('os').system('dir')"))  # 会列出当前的目录文件，如果字符串是一些删除命令，则可以把整个目录清空！

# 方式3，使用ast.literal_eval，没有json与eval的缺点，推荐使用这个
print(ast.literal_eval(target_str))
print(ast.literal_eval(target_str2))

{'h': 1, 'e': 2, 'l': 4, 'o': 5}
{'h': 1, 'e': 2, 'l': 4, 'o': 5}
{'h': 1, 'e': 2, 'l': 4, 'o': 5}
{'h': 1, 'e': 2, 'l': 4, 'o': 5}
{'h': 1, 'e': 2, 'l': 4, 'o': 5}

default_app_config = 'user.apps.UserConfig'

from django.apps import AppConfig

class UserConfig(AppConfig):
    name = 'user'
    verbose_name = '用户'

import openpyxl, sys

wb = openpyxl.load_workbook('b.xlsx')
sheet = wb['Sheet1']

# 在excel表格第二行添加新数据
addrow = 1   # 增加一行
row = 2  # 在第二行新增一行
name = 'b-back.xlsx' # 新的表名

wb1 = openpyxl.Workbook()
sheet1 = wb1['Sheet']

# 复制前row行
for i in range(1, row):
    for j in range(1, sheet.max_column + 1):
        sheet1.cell(row=i, column=j).value = sheet.cell(row=i, column=j).value


# 复制后row行
for i in range(row, sheet.max_row + 1):
    for j in range(1, sheet.max_column + 1):
        if i == row:
            # 给第row行添加新的数据
            sheet1.cell(row=row, column=j).value = '新增'
        sheet1.cell(row=i + addrow, column=j).value = sheet.cell(row=i, column=j).value

wb1.save(name)

d = {'a': 1, 'b': 2, 'c': 3, 'd': 5}

print('{a},{b}'.format(**d))
print('{0},{1},{0}'.format('a', 'b'))
print(f"{d['a']}")

1,2
a,b,a
1

SELECT * FROM a_test INNER JOIN b_test ON a_test.name = b_test.namesa

Inner join 产生的结果集中，是A和B的交集。

SELECT * FROM a_test FULL OUTER JOIN b_test ON a_test.name = b_test.name

Full outer join 产生A和B的并集。
但是需要注意的是，对于没有匹配的记录，则会以null做为值。
可以使用IF NULL判断。

SELECT * FROM a_test FULL OUTER JOIN b_test ON a_test.name = b_test.name
WHERE a_test.id IS null OR b_test.id IS null

产生A表和B表没有交集的数据集。

SELECT * FROM a_test LEFT OUTER JOIN b_test ON a_test.name = b_test.name
有些数据库可以不要OUTER
SELECT * FROM a_test LEFT  JOIN b_test ON a_test.name = b_test.name
Left outer join 产生表A的完全集，而B表中匹配的则有值，没有匹配的则以null值取代。

SELECT * FROM a_test LEFT OUTER JOIN b_test ON a_test.name = b_test.name
WHERE b_test.id IS null

产生在A表中有而在B表中没有的集合。

UNION 操作符用于合并两个或多个 SELECT 语句的结果集。
请注意，UNION 内部的 SELECT 语句必须拥有相同数量的列。
列也必须拥有相似的数据类型。
同时，每条 SELECT 语句中的列的顺序必须相同。
UNION 只选取记录，而UNION ALL会列出所有记录。

SELECT name FROM a_test UNION SELECT name FROM b_test

选取不同值

SELECT a_test.id,a_test.name  FROM a_test
UNION
SELECT b_test.id,b_test.name FROM b_test

由于 id 51 xh   与 id 4 xh 并不相同，不合并

SELECT name FROM a_test UNION ALL SELECT name FROM b_test

全部列出来

netstat -ano|findstr 8000