django create forms and form data types and attributes

08.15 self-summary

About creating relationships between different forms of django

A. Create a relationship between the different

1. One to One

For example

母表:userinfo

id	name	age
1	Joe Smith	12
2	John Doe	58

Word table: private

id	salary	sp_id
1	100	1
2	400	2

models.py

class UserInfo(models.Model):
    name = models.CharField(max_length=32, null=True)
    age  = models.IntegerField(null=True)
    
class Private(models.Model):
    salary = models.CharField(max_length=32, null=True)
    sp = models.OneToOneField("UserInfo", null=True) #oneTooneField: 一对一， 默认要求该字段必须是唯一的 unique 外键关系

Insert information

models.UserInfo.objects.create(name='张三',age=12)
models.Private.objects.create(salary=100,sp_id=1)

Inquire

#从母表查询子表中的数据

#方法1:res = models.UserInfo.objects.filter(name='张三').first().private.salary #子表表名小写.子表字段名
#方法2:res = models.UserInfo.objects.filter(name='张三').values('private__salary')

#从子表查询母表信息
#方法1:res = models.Private.objects.filter(salary='100').first().sp.name

#方法2:res = models.Private.objects.values('sp__name'):

2. to-many (by table)

models.py

class Boy(models.Model):
    bname = models.CharField(max_length=30,null=True)
    
class Girl(models.Model):
    gname = models.CharField(max_length=30,null=True)

class Boy2Girl(models.Model):
    b = models.ForeignKey('Boy',null=True)
    g = models.ForeignKey('Girl',null=True)
    #联合唯一属性
    class Meta:
        unique_together=[
            ('b','g')
        ]

Insert information

import random
boys =[
    models.Boy(bname='男1'),
    models.Boy(bname='男2'),
    models.Boy(bname='男3'),
    models.Boy(bname='男4'),
    models.Boy(bname='男5'),
    models.Boy(bname='男6')
]
res = models.Boy.objects.bulk_create(boys)

girls =[
    models.Girl(gname='女1'),
    models.Girl(gname='女2'),
    models.Girl(gname='女3'),
    models.Girl(gname='女4'),
    models.Girl(gname='女5'),
    models.Girl(gname='女6'),
    models.Girl(gname='女7'),
    models.Girl(gname='女8'),
]
models.Girl.objects.bulk_create(girls)

a = [
    models.Boy2Girl(b_id=random.randint(1,6),g_id=1),
    models.Boy2Girl(b_id=random.randint(1,6),g_id=2),
    models.Boy2Girl(b_id=random.randint(1,6),g_id=3),
    models.Boy2Girl(b_id=random.randint(1,6),g_id=4),
    models.Boy2Girl(b_id=random.randint(1,6),g_id=5),
    models.Boy2Girl(b_id=random.randint(1,6),g_id=6),
    models.Boy2Girl(b_id=random.randint(1,6),g_id=7),
    models.Boy2Girl(b_id=random.randint(1,6),g_id=8),
]
models.Boy2Girl.objects.bulk_create(a)

Inquire

#通过关系表查询,查boy位男1对于的女的信息
#方法1:res = models.Boy2Girl.objects.filter(b__bname='男1').values('g__gname')

#方法2:
 res = models.Boy2Girl.objects.filter(b__bname='男1').all()
 for a in res:
    print(res.g.gname)
    
#通过boy表查女的信息
#方法1:    res = models.Boy.objects.filter(bname='男1').values('boy2girl__g__gname')

#方法2:
    res = models.Boy.objects.filter(bname='男1').all()
    for a in res:
        for b in a.boy2girl_set.all():
            print(b.g.gname)

3. to-many (not through a relational table)

models.py

class Boy1(models.Model):
    bname = models.CharField(max_length=32, null=True)
    g = models.ManyToManyField('Girl', null=True)
 #他会生成一个boy1_g的表

class Girl1(models.Model):
    gname = models.CharField(max_length=32, null=True)

Insert information

boys =[
    models.Boy(bname='男1'),
    models.Boy(bname='男2'),
    models.Boy(bname='男3'),
    models.Boy(bname='男4'),
    models.Boy(bname='男5'),
    models.Boy(bname='男6')
]
res = models.Boy1.objects.bulk_create(boys)
#
girls =[
    models.Girl(gname='女1'),
    models.Girl(gname='女2'),
    models.Girl(gname='女3'),
    models.Girl(gname='女4'),
    models.Girl(gname='女5'),
    models.Girl(gname='女6'),
    models.Girl(gname='女7'),
    models.Girl(gname='女8'),
]
models.Girl1.objects.bulk_create(girls)

Established relationship between the two

• Remove the objects of boy
• G then select the objects, and then the Add 添加| 删除| 查询Girl's id

Add (add)

models.Boy1.objects.filter(bname='男1').first().g.add(1,2,3,4,5,2) #会自动去重保持唯一性也不会因为相同而报错

Delete (remove)

models.Boy1.objects.filter(bname='男1').first().g.remove(1)

Query (all)

models.Boy1.objects.filter(bname='男1').first().g.all()

Clear (clear)

models.Boy1.objects.filter(bname='男1').first().g.clear() #清除所有

important point

add add time if there will be automatically de-emphasis, he comes with a unique joint effect

4. many

https://www.cnblogs.com/pythonywy/p/11353202.html see here

And two .mysql djamgo-orm data type correspondence relationship

type of data	mysql	djamgo-snake
digital	tinyint	does not exist
-	smallint	SmallIntegerField (Signed) PositiveSmallIntegerField (no sign)
-	mediumint	does not exist
-	int （unsigned）	IntegerField (Signed) PositiveIntegerField (no sign)
-	bigint	BigIntegerField (Signed) PositiveBigIntegerField (no sign)
-	decimal	DecimalField
-	float	FloatField
-	double	does not exist
String	char	does not exist
-	varchar	CharField
-	text	TextField
The date and time	date	DateField
-	datetime	DateTimeField
-	timestamp	does not exist

And three .mysql djamgo-orm data corresponding to the type attribute

null                数据库中字段是否可以为空
db_column           数据库中字段的列名
default             数据库中字段的默认值
primary_key         数据库中字段是否为主键
db_index            数据库中字段是否可以建立索引
unique              数据库中字段是否可以建立唯一索引


class Meta:
### 联合唯一索引
unique_together=[
('b', 'g')
]

#### 联合索引
index_together = [
('b', 'g')
]

Four .djamgo data types that are only available in the admin

• EmailField (CharField): 字符串类型correspondence information is not verified mail format
• IPAddressField (Field,): 字符串类型, Django Admin and ModelForm provides verification mechanism IPV4
• GenericIPAddressField (Field,): 字符串类型, and the Django the Admin ModelForm Ipv4 and Ipv6 provide verification
  • parameter:
    • protocol: specifies Ipv4 or Ipv6, 'both', "ipv4", "ipv6"
    • unpack_ipv4: as if specified as True, then enter :: ffff: 192.0.2.1 when resolves to 192.0.2.1, open thorn function, protocol = "both"
• URLField (CharField): 字符串类型, Django Admin and verification URL provided ModelForm
• SlugField (as CharField): 字符串类型, in the Django ModelForm the Admin and a verification support letters, numbers, underscore, hyphen (minus)
• CommaSeparatedIntegerField (CharField): 字符串类型, digital format must be comma-separated
• UUIDField (Field,): 字符串类型, and the Django ModelForm the Admin provides verification of the UUID format
• That FilePathField will (Field,): 字符串, and the Django ModelForm provide the Admin functions to read the file folder
  • parameter:
    • path: file path
    • match = None: Match Regular
    • recursive = False: The following folders recursively
    • allow_files = True: Allow file
    • allow_folders = False: Allow file folder
• ImageField (FileField): 字符串类型path stored in the database, upload files to a specified directory
  • parameter:
    • Save the file upload path: upload_to = ""
    • storage = None: storage component, the default django.core.files.storage.FileSystemStorage
    • ImageField (FileField): database field names highly conserved upload pictures (string)
    • height_field = None: save the width of the database field name to upload your pictures (string)

Five .djamgo properties that are only available in the admin

• verbose_name: field names that appear in Admin

• blank: Admin whether user allowed to enter the air

• editable: Admin can edit whether

• help_text: Admin in the message field

• choices: Admin display content of the selection box, does not change the data in memory to avoid cross-table operation

  • Such as: gf = models.IntegerField (choices = [(0, 'Sui He'), (1, 'large cousin'),], default = 1)

• error_messages: custom error message (dictionaries), you want to customize the error message displayed;

  • Import RegexValidator django.core.validators from
    from django.core.validators Import The EmailValidator, URLValidator, DecimalValidator, MaxLengthValidator, MinLengthValidator, MaxValueValidator, MinValueValidator
    such as:
    Test = models.CharField (
    MAX_LENGTH 32 =,
    error_messages, = {
    'C1': 'wrong priority information. 1 ',
    ' C2 ':' priority error information 2 ',
    ' C3 ':' priority error information. 3 ',
    },
    validators = [
    RegexValidator (REGEX =' root_ \ D + ', message =' wrong ', code = 'C1'),
    RegexValidator (REGEX = 'root_112233 \ D +', Message = 'and wrong', code = 'C2'),
    the EmailValidator (Message = 'and wrong', code = 'C3'),]
    )

  ​