pymongo的使用

一、连接数据库

import pymongo

if __name__ == "__main__":
    # 创建连接
    client = pymongo.MongoClient(host='localhost', port=27017)
    # 指定连接的数据库test
    db = client.test
    # 指定的集合(类似表)
    collection = db.scrapy_items
    # 利用集合来操作数据库
    # result = collection.find()
    # for i in result:
    #     print(i)
    result1 = collection.find_one({'title': '运维学python之爬虫基础篇（一）开篇'})
    print(result1)

二、把连接数据库的封装到一个包下

• 1、连接数据库

  import pymongo
  
  class PymongoDb(object):
      def __init__(self):
          self.host = 'localhost'
          self.port = 27017
  
      def collection(self):
          # 创建连接
          client = pymongo.MongoClient(host=self.host, port=self.port)
          # 使用哪个数据库
          db = client.test
          # 指定表
          collection = db.mongo_item
          return collection
  

三、操作数据

• 1、插入单条数据

  from day10.db.pymongo_db import PymongoDb
  
  if __name__ == '__main__':
      collection = PymongoDb().collection()
      student = {
          'id': '20170101',
          'name': '哈哈',
          'age': 30,
          'gender': '女'
      }
      result = collection.insert(student)
      print(result)
  

• 2、插入多条数据

  from day10.db.pymongo_db import PymongoDb
  
  if __name__ == "__main__":
      collection = PymongoDb().collection()
      student1 = {
          'id': '20170101',
          'name': 'Jordan',
          'age': 20,
          'gender': 'male'
      }
  
      student2 = {
          'id': '20170202',
          'name': 'Mike',
          'age': 21,
          'gender': 'male'
      }
      result = collection.insert([student1, student2])
      print(result)
  

• 3、使用insert_one插入数据

  from day10.db.pymongo_db import PymongoDb
  
  if __name__ == "__main__":
      collection = PymongoDb().collection()
      student = {
          'name': '张三',
          'age': 20,
          'gender': '男'
      }
      result = collection.insert_one(student)
      print(result)
  

• 4、使用insert_many插入多条数据

  from day10.db.pymongo_db import PymongoDb
  
  if __name__ == "__main__":
      collection = PymongoDb().collection()
      student1 = {
          'id': '20170101',
          'name': 'Jordan',
          'age': 20,
          'gender': 'male'
      }
  
      student2 = {
          'id': '20170202',
          'name': 'Mike',
          'age': 21,
          'gender': 'male'
      }
      result = collection.insert_many([student1, student2])
      print(result.inserted_ids)
  

• 5、查询单条数据

  from day10.db.pymongo_db import PymongoDb
  
  if __name__ == "__main__":
      collection = PymongoDb().collection()
      result = collection.find_one({'name': '张三'})
      print(result)
  

• 6、find({})查询数据

  from day10.db.pymongo_db import PymongoDb
  
  if __name__ == "__main__":
      collection = PymongoDb().collection()
      result = collection.find({'age': 20})
      print(result)
      for i in result:
          print(i)
  

• 7、条件查询

  • $lt 小于 {'age': {'$lt': 20}}
  • $gt 大于 {'age': {'$gt': 20}}
  • $lte 小于等于 {'age': {'$lte': 20}}
  • $gte 大于等于 {'age': {'$gte': 20}}
  • $ne 不等于 {'age': {'$ne': 20}}
  • $in 在范围内 {'age': {'$in': [20, 23]}}
  • $nin 不在范围内 {'age': {'$nin': [20, 23]}}

  from day10.db.pymongo_db import PymongoDb
  
  if __name__ == "__main__":
      collection = PymongoDb().collection()
      result = collection.find({'age': {'$gt': 20}})
      for i in result:
          print(i)
  

• 8、关于计数

  from day10.db.pymongo_db import PymongoDb
  
  if __name__ == "__main__":
      collection = PymongoDb().collection()
      result = collection.find().count()
      print(result)
      result1 = collection.find({'age': {'$gt': 20}}).count()
      print(result1)
  

• 9、排序操作

  import pymongo
  
  from day10.db.pymongo_db import PymongoDb
  
  if __name__ == "__main__":
      collection = PymongoDb().collection()
      result = collection.find().sort('age', pymongo.ASCENDING)
      for i in result:
          print(i)
  

• 10、修改数据

  from day10.db.pymongo_db import PymongoDb
  
  if __name__ == "__main__":
      collection = PymongoDb().collection()
      result = collection.find_one({'name': '张三'})
      result['age'] = 30
      result1 = collection.update({'name': '张三'}, result)
      print(result1)
  

• 11、删除数据

  from day10.db.pymongo_db import PymongoDb
  
  if __name__ == "__main__":
      collection = PymongoDb().collection()
      result = collection.remove({'name': '张三'})
      print(result)