Use of Python database Pymongo

Two points must be guaranteed before use:

A MONGODB database is installed on the computer, and Python has the Pymongo package installed.

B Open Mongod.exe

1 Creating a Client

Client = Pymongo. Mongoclient (' localhost ', 27017)
#pymongo. Mongoclient () default is local client ' localhost ' when no parameters are taken: 27017

2 Correlation Database

Associated database There are two ways to create a database  and connect to an existing database: Create a database runoob:db = client[' Runoob ') connect an existing database runoocdb = CLIENT.RUNOOC

3 Association Collections

Associative collections have two ways of creating collections  and connecting existing collections: Creating collections Run:collection = Db[' run '] connecting existing collections Runocollection = Db.runo

4 Increase

#插入单条数据collection. Insert ({' name ': ' Lili ', ' age ': +}) #插入多条数据collection. Insert ({' name ': ' Lili ', ' age ': +}, {' Location ': [123,456], ' Dad ': ' Me '}

LST = [{' name ': ' Lili ', ' Age ': $}, {' Location ': [123,456], ' Dad ': ' Me '}]
Collection.insert (LST) #变量式doc = {    ' name ': ' Lili ',    ' age ': +,    ' location ': [123,456],    ' Dad ': ' Me '    }collection.insert (DOC)

5 Check

#单一条件查找for I in Collection.find ({' Age ': '):p rint i#& Find for I-collection.find ({' Age ': $, ' name ': ' Lili '}):p rint i# Or look for the for I in Collection.find ({' $or ': [{' {': ') ' ({' name ': ']} '):p rint i# & and OR with the Collection.find ({"likes": {' $gt ' : ' $or ': [{' Age ': $}, {' Age ': '} '}). #查一个具体对象collection. Find_one ({' Age ': ') ' #返回值是一个具体的对象

6 change

#更新一条数据collection. Update ({' Age ': $}, {' $set ': {' age ': +}}) #用 ' age ': 28 replace the found first ' age ': 24# update to record collection.update ({' Age ': $}, {' $set ': {' age ': Multi=true}}, and ' age ': 28 replaces all ' age ': 24

7 by deleting

#删掉所有 {' Age ': 28} Data Collection.remove ({' Age ': ') ' #删除数据集collection. Drop ()

8 Other

Sort: Use the sort () method in MongoDB to sort the data, the sort () method can specify the sorted field by parameter, and use 1 and-one to specify how to sort, where 1 is ascending, and 1 is descending.

For I in Collection.find (). Sort ([("Age", 1)]):    print (i)

Limit and Skip:

The #limit () method is used to read a specified number of data #skip () methods used to skip a specified number of data # The following means that after skipping two data, read 6 for I in My_set.find (). Skip (2). Limit (6):    print (i)

Condition operators for MongoDB:

#    (>)  greater than-$gt #    (<)  less than-$lt #    (>=)  greater than or equal to-$gte #    (<=)  less than or equal-$lte # Example: Querying all records of age greater than 25 in a collection for I in My_set.find ({"Age": {"$GT": +}}):    print (i)

Type (judging types)

#找出name的类型是String的  will only find out if name is a string type for I in My_set.find ({' name ': {' $type ': 2}}):    print (i) type table double    1     String    2     object    3     Array    4     Binary data    5     Undefined    6 deprecated    Object ID    7     Boolean    8     Date    9     Null     Regular Expression     One JavaScript     Symbol for     JavaScript (with scope)     32-bit integer     Timestamp     64-bit integer     Min key    255    Query With-1.max key    127

Use of Python database Pymongo