Python MongoDB create a collection

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chapter

• Python MySQL entry
• Python MySQL create database
• Python MySQL create table
• Python MySQL Insert Table
• Python MySQL Select
• Python MySQL Where
• Python MySQL Order By
• Python MySQL Delete
• Python MySQL drop table
• Python MySQL Update
• Python MySQL Limit
• Python MySQL Join

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Similar to in MongoDB set of SQL database tables.

Create Collection

To create a collection in MongoDB, a database object, passing the name of the collection to be created.

If no collection exists with the same name, MongoDB will create it.

Examples

Create a collection called "customers" are:

import pymongo

myclient = pymongo.MongoClient("mongodb://192.168.31.154:27017/")
mydb = myclient["mydatabase"]

mycol = mydb["customers"]

IMPORTANT : MongoDB in, not really create a collection before you add content!

MongoDB will wait until after the insertion of a document, really create a collection.

Check whether there is a collection

Remember : MongoDB, the collection is created only when you add content, if this is the first time the collection is created, you should add content (the next chapter, creating a document), and then check whether the collection exists!

The existence of a set of inspection database, we can list all the database collections:

Examples

Returns the database of all collections:

print(mydb.list_collection_names())

Or you can check whether there is a collection:

Examples

Check the "customers" the existence of the collection:

collist = mydb.list_collection_names()
if "customers" in collist:
  print("这个集合存在")