Django项目之CRM客户关系管理——表结构的设计及MySQL的连接

先附上整个系统的表结构设计：

from django.db import models
from django.contrib.auth.models import User

# Create your models here.

class Customer(models.Model):
    """客户信息表"""
    name = models.CharField(max_length=32,blank=True,null=True)#blank的作用是，admin操作时，允许null
    qq = models.CharField(max_length=64,unique=True)
    qq_name = models.CharField(max_length=32,blank=True,null=True)
    phone = models.CharField(max_length=64,blank=True,null=True)
    source_choices = ((0,'转介绍'),
                      (1, 'QQ群'),
                      (2, '官网'),
                      (3, '百度推广'),
                      (4, '51CTO'),
                      (5, '知乎'),
                      (6, '市场推广'),
                      )
    source = models.SmallIntegerField(choices=source_choices)
    referral_form = models.CharField(verbose_name="转介绍人qq",max_length=64,null=True,blank=True)
    consult_course = models.ForeignKey("Course",verbose_name="咨询课程",on_delete=models.CASCADE)
    content = models.TextField(verbose_name="咨询详情")
    tags = models.ManyToManyField("Tag",blank=True,null=True)
    consultant = models.ForeignKey("UserProfile",on_delete=models.CASCADE)#课程顾问,外键账户表
    memo = models.TextField(blank=True,null=True)#备注
    date = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return self.qq

class Tag(models.Model):
    name = models.CharField(unique=True,max_length=32)

    def __str__(self):
        return self.name

class CustomerFollowUp(models.Model):
    """客户跟进表"""
    customer = models.ForeignKey("Customer",on_delete=models.CASCADE)
    content = models.TextField(verbose_name="跟进内容")
    consultant = models.ForeignKey("UserProfile", on_delete=models.CASCADE)#课程顾问,外键账户表
    date = models.DateTimeField(auto_now_add=True)
    intention_choices = ((0,'2周内报名'),
                        (1,'1个月内报名'),
                        (2,'近期无报名计划'),
                        (3,'已在其它机构报名'),
                        (4,'已报名'),
                        (5,'已拉黑'),
                        )
    intention = models.SmallIntegerField(choices=intention_choices)

    def __str__(self):
        return "<%s : %s>" %(self.customer.qq, self.intention)

class Course(models.Model):
    """课程表"""
    name = models.CharField(max_length=64,unique=True)
    price = models.PositiveSmallIntegerField()#学费，positive表示正数
    period = models.PositiveSmallIntegerField(verbose_name="周期（月）")#周期
    outline = models.TextField()#大纲

    def __str__(self):
        return self.name

class Branch(models.Model):
    """校区表"""
    name = models.CharField(max_length=128,unique=True)
    addr = models.CharField(max_length=128)

    def __str__(self):
        return self.name

class ClassList(models.Model):
    """班级表"""
    branch = models.ForeignKey("Branch",on_delete=models.CASCADE,verbose_name="校区")
    course = models.ForeignKey("Course",on_delete=models.CASCADE)
    class_type_choices = ((0,'面授(脱产)'),
                          (1,'面授(周末)'),
                          (2,'网络班'),
                          )
    class_type = models.PositiveSmallIntegerField(choices=class_type_choices,verbose_name="班级类型")
    semester = models.PositiveSmallIntegerField(verbose_name="学期")
    teachers = models.ManyToManyField("UserProfile")
    start_date = models.DateField(verbose_name="开班日期")
    end_date = models.DateField(verbose_name="结业日期",blank=True,null=True)

    def __str__(self):
        return "%s %s %s" %(self.branch,self.course,self.semester)

    class Meta:
        unique_together = ('branch','course','semester')

class CourseRecord(models.Model):
    """上课记录"""
    from_class = models.ForeignKey("ClassList",verbose_name="班级",on_delete=models.CASCADE)
    day_num = models.PositiveSmallIntegerField(verbose_name="第几节（天）")
    teacher = models.ForeignKey("UserProfile",on_delete=models.CASCADE)
    has_homework = models.BooleanField(default=True)
    homework_title = models.CharField(max_length=128,blank=True,null=True)
    homework_content = models.TextField(blank=True,null=True)
    outline = models.TextField(verbose_name="本节课大纲")
    date = models.DateField(auto_now_add=True)

    def __str__(self):
        return "%s %s " %(self.from_class,self.day_num)

    class Meta:
        unique_together = ("from_class","day_num")

class StudyRecord(models.Model):
    """学习记录表"""
    student = models.ForeignKey("Enrollment",on_delete=models.CASCADE)
    course_record = models.ForeignKey("CourseRecord",on_delete=models.CASCADE)
    attendance_choices = ((0,'已签到'),
                         (1,'迟到'),
                         (2,'缺勤'),
                         (3,'早退'),
                         )
    attendance = models.SmallIntegerField(choices=attendance_choices,default=0)
    score_choices = ((100,"A+"),
                     (90,"A"),
                     (85,"B+"),
                     (80,"B"),
                     (75,"B-"),
                     (70,"C+"),
                     (60,"C"),
                     (40,"C-"),
                     (0,"N/A"),#Not Available
                     (-50,"D"),
                     (-100,"COPY"),
                     )
    score = models.SmallIntegerField(choices=score_choices)
    memo = models.TextField(blank=True,null=True)#备注
    date = models.DateField(auto_now_add=True)

    def __str__(self):
        return "%s %s %s" %(self.student,self.course_record,self.score)

class Enrollment(models.Model):
    """报名表"""
    customer = models.ForeignKey("Customer",on_delete=models.CASCADE)
    enrolled_class = models.ForeignKey("ClassList",verbose_name="所报班级",on_delete=models.CASCADE)
    consultant = models.ForeignKey("UserProfile",verbose_name="课程顾问",on_delete=models.CASCADE)
    contract_agreed = models.BooleanField(default=False,verbose_name="学员已同意合同")
    contract_approved = models.BooleanField(default=False,verbose_name="合同已审核")
    date = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return "%s %s" %(self.customer,self.enrolled_class)

    class Meta:
        unique_together = ("customer","enrolled_class")

class Payment(models.Model):
    """缴费记录"""
    customer = models.ForeignKey("Customer",on_delete=models.CASCADE)
    course = models.ForeignKey("Course",on_delete=models.CASCADE)
    amount = models.PositiveIntegerField(verbose_name="数额",default=500)#交的钱,定金500
    consultant = models.ForeignKey("UserProfile",on_delete=models.CASCADE)
    date = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return "%s %s" %(self.customer,self.amount)

class UserProfile(models.Model):
    """账号表"""
    user = models.OneToOneField(User,on_delete=models.CASCADE)
    name = models.CharField(max_length=32)
    roles = models.ManyToManyField("Role",null=True,blank=True)

    def __str__(self):
        return self.name

class Role(models.Model):
    """角色表"""
    name = models.CharField(max_length=32,unique=True)

    def __str__(self):
        return self.name

接下来连接MySQL数据库：

第一步

配置settings模块：

首先可能会遇到pip需要更新的提示，利用如下代码解决：

python -m pip install --upgrade pip

pip install 包名-i http://pypi.douban.com/simple/ --trusted-host pypi.douban.com

1.python2中Django连接数据库使用的是MySQLdb这个模块

2.python3.5+中Django连接数据库使用的是pymsql这个模块，并且不再支持MySQLdb

第二步

于是，我们需要下载pymysql这个模块
第一步：

pip install pymysql

第二步，在_init_.py文件中添加代码:

import pymysql
pymysql.install_as_MySQLdb()

第三步

这个时候执行python manage.py makemigrations 可能会报如下错误：

django.core.exceptions.ImproperlyConfigured: mysqlclient 1.3.13 or newer is required; you have 0.9.3.

第一步：

# 找到base.py文件，注释掉 base.py 中如下部分（35/36行）
if version < (1, 3, 3):
     raise ImproperlyConfigured("mysqlclient 1.3.3 or newer is required; you have %s" % Database.__version__)

第二步：

#找到operations.py文件（146行），将decode改为encode
#linux vim 查找快捷键：？decode
if query is not None:
    query = query.decode(errors='replace')
return query
#改为
if query is not None:
    query = query.encode(errors='replace')
return query

最后

执行语句，成功连接数据库：

python manage.py makemigrations

python manage.py migrate