1.Pymongo 安装
安装pymongo：
pip install pymongo
- PyMongo是驱动程序，使python程序能够使用Mongodb数据库，使用python编写而成；
2.Pymongo 方法
insert_one()：插入一条记录；insert()：插入多条记录；find_one()：查询一条记录，不带任何参数返回第一条记录，带参数则按条件查找返回；find()：查询多条记录，不带参数返回所有记录，带参数按条件查找返回；count()：查看记录总数；create_index()：创建索引；update_one()：更新匹配到的第一条数据；update()：更新匹配到的所有数据；remove()：删除记录，不带参表示删除全部记录，带参则表示按条件删除；delete_one()：删除单条记录；delete_many()：删除多条记录；
3.Pymongo 中的操作
from pymongo import MongoClient
connect = MongoClient(host='localhost', port=27017, username="root", password="123456")
connect = MongoClient('mongodb://localhost:27017/', username="root", password="123456")
print(connect.list_database_names())
test_db = connect['test']
collection = test_db['students']
- 插入一行document, 查询一行document，取出一行document的值
from pymongo import MongoClient
from datetime import datetime
connect = MongoClient(host='localhost', port=27017, username="root", password="123456",)
- 插入多行documents, 查询多行document， 查看collections有多少行document
from pymongo import MongoClient
from datetime import datetime
connect = MongoClient(host='localhost', port=27017, username="root", password="123456",)
from pymongo import MongoClient
from datetime import datetime
connect = MongoClient(host='localhost', port=27017, username="root", password="123456",)
from pymongo import MongoClient
import pymongo
from datetime import datetime
connect = MongoClient(host='localhost', port=27017, username="root", password="123456",)
from pymongo import MongoClient
connect = MongoClient(host='localhost', port=27017, username="root", password="123456",)
from pymongo import MongoClient
connect = MongoClient(host='localhost', port=27017, username="root", password="123456",)
4.MongoDB ODM 详解
- MongoDB ODM 与 Django ORM使用方法类似；
- MongoEngine是一个对象文档映射器，用Python编写，用于处理MongoDB；
- MongoEngine提供的抽象是基于类的，创建的所有模型都是类；
BinaryField
BooleanField
ComplexDateTimeField
DateTimeField
DecimalField
DictField
DynamicField
EmailField
EmbeddedDocumentField
EmbeddedDocumentListField
FileField
FloatField
GenericEmbeddedDocumentField
GenericReferenceField
GenericLazyReferenceField
GeoPointField
ImageField
IntField
ListField:可以将自定义的文档类型嵌套
MapField
ObjectIdField
ReferenceField
LazyReferenceField
SequenceField
SortedListField
StringField
URLField
UUIDField
PointField
LineStringField
PolygonField
MultiPointField
MultiLineStringField
MultiPolygonField
5.使用mongoengine创建数据库连接
from mongoengine import connect
conn = connect(db='test', host='localhost', port=27017, username='root', password='123456', authentication_source='admin')
print(conn)
connect（db = None，alias ='default'，** kwargs ）；
db：要使用的数据库的名称，以便与connect兼容；host ：要连接的mongod实例的主机名；port ：运行mongod实例的端口；username：用于进行身份验证的用户名；password：用于进行身份验证的密码；authentication_source ：要进行身份验证的数据库；
构建文档模型，插入数据
from mongoengine import connect, \
Document, \
StringField,\
IntField, \
FloatField,\
ListField, \
EmbeddedDocumentField,\
DateTimeField, \
EmbeddedDocument
from datetime import datetime
# 嵌套文档
class Score(EmbeddedDocument):
name = StringField(max_length=50, required=True)
value = FloatField(required=True)
class Students(Document):
choice = (('F', 'female'),
('M', 'male'),)
name = StringField(max_length=100, required=True, unique=True)
age = IntField(required=True)
hobby = StringField(max_length=100, required=True, )
gender = StringField(choices=choice, required=True)
# 这里使用到了嵌套文档，这个列表中的每一个元素都是一个字典，因此使用嵌套类型的字段
score = ListField(EmbeddedDocumentField(Score))
time = DateTimeField(default=datetime.now())
if __name__ == '__main__':
connect(db='test', host='localhost', port=27017, username='root', password='123456', authentication_source='admin')
math_score = Score(name='math', value=94)
chinese_score = Score(name='chinese', value=100)
python_score = Score(name='python', value=99)
for i in range(10):
students = Students(name='robby{}'.format(i), age=int('{}'.format(i)), hobby='read', gender='M', score=[math_score, chinese_score, python_score])
students.save()
查询数据
from mongoengine import connect, \
Document, \
StringField,\
IntField, \
FloatField,\
ListField, \
EmbeddedDocumentField,\
DateTimeField, \
EmbeddedDocument
from datetime import datetime
修改、更新、删除数据
from mongoengine import connect, \
Document, \
StringField,\
IntField, \
FloatField,\
ListField, \
EmbeddedDocumentField,\
DateTimeField, \
EmbeddedDocument
from datetime import datetime
# 嵌套文档
class Score(EmbeddedDocument):
name = StringField(max_length=50, required=True)
value = FloatField(required=True)
class Students(Document):
choice = (('F', 'female'),
('M', 'male'),)
name = StringField(max_length=100, required=True, unique=True)
age = IntField(required=True)
hobby = StringField(max_length=100, required=True, )
gender = StringField(choices=choice, required=True)
# 这里使用到了嵌套文档，这个列表中的每一个元素都是一个字典，因此使用嵌套类型的字段
score = ListField(EmbeddedDocumentField(Score))
time = DateTimeField(default=datetime.now())
if __name__ == '__main__':
connect(db='test', host='localhost', port=27017, username='root', password='123456', authentication_source='admin')
specific_document = Students.objects.filter(name='robby3')
specific_document.update(set__age=100)
specific_document.update_one(set__age=100)
for document in specific_document:
document.name = 'ROBBY100'
document.save()
for document in specific_document:
document.delete()
all()：返回所有文档；all_fields()：包括所有字段；as_pymongo()：返回的不是Document实例 而是pymongo值；average()：平均值超过指定字段的值；batch_size()：限制单个批次中返回的文档数量；clone()：创建当前查询集的副本；comment()：在查询中添加注释；count()：计算查询中的选定元素；create()：创建新对象，返回保存的对象实例；delete()：删除查询匹配的文档；distinct()：返回给定字段的不同值列表；
嵌入式文档查询的方法
count()：列表中嵌入文档的数量，列表的长度；create()：创建新的嵌入式文档并将其保存到数据库中；delete()：从数据库中删除嵌入的文档；exclude(** kwargs )：通过使用给定的关键字参数排除嵌入的文档来过滤列表；first()：返回列表中的第一个嵌入文档；get()：检索由给定关键字参数确定的嵌入文档；save()：保存祖先文档；update()：使用给定的替换值更新嵌入的文档；
来源：https://www.cnblogs.com/wefeng/p/11503102.html |
發表於 2019-9-10 21:34:00