django之--choices參數

choices參數(數據庫字段設計常見)

'''
針對某個可以列舉完全的可能性字段，
只要某個字段的可能性是可以列舉完全，那麼不出意外就用choices參數
'''
class User(models.Model):
    username = models.CharField(max_length=32)
    age = models.IntegerField()
    # 性別
    gender_choices = (
        (1,'男'),
        (2,'女'),
        (3,'其他'),
    )
    gender = models.IntegerField(choices=gender_choices)
    # 成績
    score_choices = (
        ('A','優秀'),
        ('B','良好'),
        ('C','及格'),
        ('D','不合格'),
    )
    # 保證字段類型跟列舉出來的元祖第一個數據類型一致即可
    score = models.CharField(choices=score_choices,null=True)
    """
    該gender字段存的還是數字 但是如果存的數字在上面元祖列舉的範圍之內
    那麼可以非常輕鬆的獲取到數字對應的真正的內容
    
    1.gender字段存的數字不在上述元祖列舉的範圍內容
    2.如果在 如何獲取對應的中文信息
    """
    
# choices使用：通過get_字段名_display()得形式來獲取對應信息，
#            如果沒有對應關係，那麼字段裏是什麼就輸出什麼
from app01 import models
# choices在存的時候沒有列舉出來的數字也能夠存入
# models.Test_User.objects.create(username='yumi', age=18, gender=1)
# models.Test_User.objects.create(username='rem', age=17, gender=0)
# models.Test_User.objects.create(username='egon', age=18, gender=2)
# choices在取得時候，通過get_gender_display()來獲取對應信息，如果是沒有對應關係，那麼字段是什麼就輸出什麼
obj = models.Test_User.objects.filter(pk=1).first()
print(obj.get_gender_display())

# 實際項目案例
# CRM相關內部表
class School(models.Model):
    """
    校區表
    如：
        北京沙河校區
        上海校區
    """
    title = models.CharField(verbose_name='校區名稱', max_length=32)

    def __str__(self):
        return self.title

class Course(models.Model):
    """
    課程表
    如：
        Linux基礎
        Linux架構師
        Python自動化開發精英班
        Python自動化開發架構師班
        Python基礎班
        go基礎班
    """
    name = models.CharField(verbose_name='課程名稱', max_length=32)

    def __str__(self):
        return self.name

class Department(models.Model):
    """
    部門表
    市場部     1000
    銷售       1001

    """
    title = models.CharField(verbose_name='部門名稱', max_length=16)
    code = models.IntegerField(verbose_name='部門編號', unique=True, null=False)

    def __str__(self):
        return self.title

class UserInfo(models.Model):
    """
    員工表
    """

    name = models.CharField(verbose_name='員工姓名', max_length=16)
    email = models.EmailField(verbose_name='郵箱', max_length=64)
    depart = models.ForeignKey(verbose_name='部門', to="Department",to_field="code")
    user=models.OneToOneField("User",default=1)
    def __str__(self):
        return self.name

class ClassList(models.Model):
    """
    班級表
    如：
        Python全棧  面授班  5期  10000  2017-11-11  2018-5-11
    """
    school = models.ForeignKey(verbose_name='校區', to='School')
    course = models.ForeignKey(verbose_name='課程名稱', to='Course')
    semester = models.IntegerField(verbose_name="班級(期)")


    price = models.IntegerField(verbose_name="學費")
    start_date = models.DateField(verbose_name="開班日期")
    graduate_date = models.DateField(verbose_name="結業日期", null=True, blank=True)
    memo = models.CharField(verbose_name='說明', max_length=256, blank=True, null=True, )

    teachers = models.ManyToManyField(verbose_name='任課老師', to='UserInfo',limit_choices_to={'depart':1002})
    tutor = models.ForeignKey(verbose_name='班主任', to='UserInfo',related_name="class_list",limit_choices_to={'depart':1006})


    def __str__(self):
        return "{0}({1}期)".format(self.course.name, self.semester)


class Customer(models.Model):
    """
    客戶表
    """
    qq = models.CharField(verbose_name='qq', max_length=64, unique=True, help_text='QQ號必須唯一')

    name = models.CharField(verbose_name='學生姓名', max_length=16)
    gender_choices = ((1, '男'), (2, '女'))
    gender = models.SmallIntegerField(verbose_name='性別', choices=gender_choices)

    education_choices = (
        (1, '重點大學'),
        (2, '普通本科'),
        (3, '獨立院校'),
        (4, '民辦本科'),
        (5, '大專'),
        (6, '民辦專科'),
        (7, '高中'),
        (8, '其他')
    )
    education = models.IntegerField(verbose_name='學歷', choices=education_choices, blank=True, null=True, )
    graduation_school = models.CharField(verbose_name='畢業學校', max_length=64, blank=True, null=True)
    major = models.CharField(verbose_name='所學專業', max_length=64, blank=True, null=True)

    experience_choices = [
        (1, '在校生'),
        (2, '應屆畢業'),
        (3, '半年以內'),
        (4, '半年至一年'),
        (5, '一年至三年'),
        (6, '三年至五年'),
        (7, '五年以上'),
    ]
    experience = models.IntegerField(verbose_name='工作經驗', blank=True, null=True, choices=experience_choices)
    work_status_choices = [
        (1, '在職'),
        (2, '無業')
    ]
    work_status = models.IntegerField(verbose_name="職業狀態", choices=work_status_choices, default=1, blank=True,
                                      null=True)
    company = models.CharField(verbose_name="目前就職公司", max_length=64, blank=True, null=True)
    salary = models.CharField(verbose_name="當前薪資", max_length=64, blank=True, null=True)

    source_choices = [
        (1, "qq羣"),
        (2, "內部轉介紹"),
        (3, "官方網站"),
        (4, "百度推廣"),
        (5, "360推廣"),
        (6, "搜狗推廣"),
        (7, "騰訊課堂"),
        (8, "廣點通"),
        (9, "高校宣講"),
        (10, "渠道代理"),
        (11, "51cto"),
        (12, "智匯推"),
        (13, "網盟"),
        (14, "DSP"),
        (15, "SEO"),
        (16, "其它"),
    ]
    source = models.SmallIntegerField('客戶來源', choices=source_choices, default=1)
    referral_from = models.ForeignKey(
        'self',
        blank=True,
        null=True,
        verbose_name="轉介紹自學員",
        help_text="若此客戶是轉介紹自內部學員,請在此處選擇內部學員姓名",
        related_name="internal_referral"
    )
    course = models.ManyToManyField(verbose_name="諮詢課程", to="Course")

    status_choices = [
        (1, "已報名"),
        (2, "未報名")
    ]
    status = models.IntegerField(
        verbose_name="狀態",
        choices=status_choices,
        default=2,
        help_text=u"選擇客戶此時的狀態"
    )

    consultant = models.ForeignKey(verbose_name="課程顧問", to='UserInfo', related_name='consultanter',limit_choices_to={'depart':1001})

    date = models.DateField(verbose_name="諮詢日期", auto_now_add=True)
    recv_date = models.DateField(verbose_name="當前課程顧問的接單日期", null=True)
    last_consult_date = models.DateField(verbose_name="最後跟進日期", )

    def __str__(self):
        return self.name

class ConsultRecord(models.Model):
    """
    客戶跟進記錄
    """
    customer = models.ForeignKey(verbose_name="所諮詢客戶", to='Customer')
    consultant = models.ForeignKey(verbose_name="跟蹤人", to='UserInfo',limit_choices_to={'depart':1001})
    date = models.DateField(verbose_name="跟進日期", auto_now_add=True)
    note = models.TextField(verbose_name="跟進內容...")

    def __str__(self):
        return self.customer.name + ":" + self.consultant.name

class Student(models.Model):
    """
    學生表（已報名）
    """
    customer = models.OneToOneField(verbose_name='客戶信息', to='Customer')
    class_list = models.ManyToManyField(verbose_name="已報班級", to='ClassList', blank=True)

    emergency_contract = models.CharField(max_length=32, blank=True, null=True, verbose_name='緊急聯繫人')
    company = models.CharField(verbose_name='公司', max_length=128, blank=True, null=True)
    location = models.CharField(max_length=64, verbose_name='所在區域', blank=True, null=True)
    position = models.CharField(verbose_name='崗位', max_length=64, blank=True, null=True)
    salary = models.IntegerField(verbose_name='薪資', blank=True, null=True)
    welfare = models.CharField(verbose_name='福利', max_length=256, blank=True, null=True)
    date = models.DateField(verbose_name='入職時間', help_text='格式yyyy-mm-dd', blank=True, null=True)
    memo = models.CharField(verbose_name='備註', max_length=256, blank=True, null=True)

    def __str__(self):
        return self.customer.name

class ClassStudyRecord(models.Model):
    """
    上課記錄表 （班級記錄）
    """
    class_obj = models.ForeignKey(verbose_name="班級", to="ClassList")
    day_num = models.IntegerField(verbose_name="節次", help_text=u"此處填寫第幾節課或第幾天課程...,必須爲數字")
    teacher = models.ForeignKey(verbose_name="講師", to='UserInfo',limit_choices_to={'depart':1002})
    date = models.DateField(verbose_name="上課日期", auto_now_add=True)

    course_title = models.CharField(verbose_name='本節課程標題', max_length=64, blank=True, null=True)
    course_memo = models.TextField(verbose_name='本節課程內容概要', blank=True, null=True)
    has_homework = models.BooleanField(default=True, verbose_name="本節有作業")
    homework_title = models.CharField(verbose_name='本節作業標題', max_length=64, blank=True, null=True)
    homework_memo = models.TextField(verbose_name='作業描述', max_length=500, blank=True, null=True)
    exam = models.TextField(verbose_name='踩分點', max_length=300, blank=True, null=True)

    def __str__(self):
        return "{0} day{1}".format(self.class_obj, self.day_num)

class StudentStudyRecord(models.Model):
    '''
    學生學習記錄
    '''
    classstudyrecord = models.ForeignKey(verbose_name="第幾天課程", to="ClassStudyRecord")
    student = models.ForeignKey(verbose_name="學員", to='Student')
    record_choices = (('checked', "已簽到"),
                      ('vacate', "請假"),
                      ('late', "遲到"),
                      ('noshow', "缺勤"),
                      ('leave_early', "早退"),
                      )
    record = models.CharField("上課紀錄", choices=record_choices, default="checked", max_length=64)
    score_choices = ((100, 'A+'),
                     (90, 'A'),
                     (85, 'B+'),
                     (80, 'B'),
                     (70, 'B-'),
                     (60, 'C+'),
                     (50, 'C'),
                     (40, 'C-'),
                     (0, ' D'),
                     (-1, 'N/A'),
                     (-100, 'COPY'),
                     (-1000, 'FAIL'),
                     )
    score = models.IntegerField("本節成績", choices=score_choices, default=-1)
    homework_note = models.CharField(verbose_name='作業評語', max_length=255, blank=True, null=True)
    note = models.CharField(verbose_name="備註", max_length=255, blank=True, null=True)

    homework = models.FileField(verbose_name='作業文件', blank=True, null=True, default=None)
    stu_memo = models.TextField(verbose_name='學員備註', blank=True, null=True)
    date = models.DateTimeField(verbose_name='提交作業日期', auto_now_add=True)

    def __str__(self):
        return "{0}-{1}".format(self.classstudyrecord, self.student)
         
"""
chocies參數使用場景是非常廣泛的
"""

MTV與MVC模型

# MTV:Django號稱是MTV模型
M:models
T:templates
V:views
# MVC:其實django本質也是MVC
M:models
V:views
C:controller（urls.py）
  
# vue框架:MVVM模型

多對多關係的三種創建方式

# 全自動：利用orm自動幫我們創建第三張關係表
class Student(models.Model):
    stu_name = models.CharField(max_length=30)
    course = models.ManyToManyField('Course')

class Course(models.Model):
    cname = models.CharField(max_length=30)


# 純手動
class Student(models.Model):
    stu_name = models.CharField(max_length=30)
    course = models.ManyToManyField('Course')

class Course(models.Model):
    cname = models.CharField(max_length=30)
    
class Student2Course(models.Model):
    stu_id = models.ForeignKey(to='Student')
    cid = models.ForeignKey(to='Course')
    
    
# 半自動
class Student(models.Model):
    stu_name = models.CharField(max_length=30)
    course = models.ManyToManyField('Course',
                                    through='Student2Course',
                                    through_fields=('stu', 'course'))
    
class Course(models.Model):
    cname = models.CharField(max_length=30)
    
class Student2Course(models.Model):
    # 關聯字段
    stu = models.ForeignKey(to='Student')
    course = models.ForeignKey(to='Course')
    
    
'''
全自動
    優點：代碼書寫便捷，orm都幫我寫好了，並且還給我們提供了操作第三張表得方法
    缺點：可擴展性太差，無發對第三張關係表添加字段

純手動（不建議使用）
    優點：由於所有的外鍵都是自己寫，可擴展性加強了
    缺點：無法使用orm所提供的簡單方法了
        (正反向查詢、雙下劃線查詢、set、add、remove、claear)

半自動（推薦使用、留後路）
    優點：可以使用orm提供的正反向查詢，也增強了可擴展性
    缺點：但是orm提供的set、add、remove、claear這四個方法無法使用
    through參數後面跟自己建的第三張關係表
    through_fields參數後面跟元組
        元組內字段的先後順序判斷：
            本質：通過第三張表查詢對應的表，需要哪個字段就把哪個字段放在前面
            大白話：當前表是誰 就把對應的關聯字段放前面
'''