MongoDB Basic Operations (i)

1.1. MongoDBBasic Operations1.1.1. Create a database

Syntax: Use [DatabaseName]

> Use admin

Switched to DB admin

> Use RGF; # CREATE DATABASE RGF

Switched to DB RGF

> Db.person.insert ({name: ' Xuanxuan '}) # Create a collection person in RGF and insert a row of data

Writeresult ({"ninserted": 1})

1.1.2. View all Databases

Syntax: Show DBS

> Show DBS;

Admin (empty)

Local 0.078GB

RGF 0.078GB

Test 0.078GB

1.1.3. add a collection to the specified database and add records

Syntax: db.[ Documentname].insert ({...})

> Db.person.insert ({age: ' 10 '});

Writeresult ({"ninserted": 1})

>db.person.insert ({age: '},{sex: ' Male '});

Writeresult ({"ninserted": 1})

1.1.4. View all documents in the database

Syntax: showcollections;

> Show Collections;

Person

System.indexes

1.1.5. querying data for a specified document

Grammar:

Check all :

Db. [Documnetname].find ();

Query the first piece of data:

Db. [Documentname].findone ()

> Db.system.indexes.find ()

{"V": 1, "key": {"_id": 1}, "name": "_id_", "ns": "Rgf.person"}

> Db.person.find ()

{"_id": ObjectId ("549b31b7ff3a181677422f47"), "name": "Xuanxuan"}

{"_id": ObjectId ("549b32ebff3a181677422f48"), "Age": "10"}

{"_id": ObjectId ("549b3352ff3a181677422f49"), "Age": "10"}

> Db.person.insert ({age: '},{sex: ' Male '});

Writeresult ({"ninserted": 1})

> Db.person.findone ()

2014-12-25t05:58:14.270+0800 typeerror:property ' FindOne ' of object Rgf.person is not a function

> Db.person.findOne ()

{"_id": ObjectId ("549b31b7ff3a181677422f47"), "name": "Xuanxuan"}

Note that the O in the function FindOne must be capitalized.

1.1.6. Update document Data

Grammar:

db. [Documentname].update ({ query condition },{ update content })

Cases:

VarP = Db.person.findOne ()

Db.person.update (p,{name: "Gaogao"})

>db.person.update ({name: ' Xuanxuan '},{$set: {name: ' Zhaoxing '}})

Writeresult ({"nmatched": 1, "nupserted": 0, "nmodified": 1})

> Db.person.findOne ()

{"_id": ObjectId ("549b31b7ff3a181677422f47"), "name": "Zhaoxing"}

>

> var p = db.person.findOne ()

> P

{"_id": ObjectId ("549b31b7ff3a181677422f47"), "name": "Zhaoxing"}

>db.person.update (p,{name: "Gaogao"})

Writeresult ({"nmatched": 1, "nupserted": 0, "nmodified": 1})

> P

{"_id": ObjectId ("549b31b7ff3a181677422f47"), "name": "Zhaoxing"}

> var p = db.person.findOne ()

Note that you need to assign variables again at this time

> P

{"_id": ObjectId ("549b31b7ff3a181677422f47"), "name": "Gaogao"}

>

{"_id": ObjectId ("549b31b7ff3a181677422f47"), "name": "Gaogao2", "Age": 2}

MONGO changes the first data by default.

>db.person.update ({age: "},{$set: {age:5}})

Writeresult ({"nmatched": 1, "nupserted": 0, "nmodified": 1})

> Db.person.find ()

{"_id": ObjectId ("549b32ebff3a181677422f48"), "Age": 5}

{"_id": ObjectId ("549b3352ff3a181677422f49"), "Age": "10"}

{"_id": ObjectId ("549b3508ff3a181677422f4a"), "Age": "20"}

{"_id": ObjectId ("549b31b7ff3a181677422f47"), "name": "Gaogao2", "Age": 2}

>

1.1.7. Delete data in a document

Grammar:

Db. [Documentname].remove ({...})

> Db.person.find ()

{"_id": ObjectId ("549b32ebff3a181677422f48"), "Age": 5}

{"_id": ObjectId ("549b3352ff3a181677422f49"), "Age": "10"}

{"_id": ObjectId ("549b3508ff3a181677422f4a"), "Age": "20"}

{"_id": ObjectId ("549b31b7ff3a181677422f47"), "name": "Gaogao2", "Age": 2}

> Db.person.remove ({Age: "10"})

Writeresult ({"nremoved": 1})

> Db.person.find ()

{"_id": ObjectId ("549b32ebff3a181677422f48"), "Age": 5}

{"_id": ObjectId ("549b3508ff3a181677422f4a"), "Age": "20"}

{"_id": ObjectId ("549b31b7ff3a181677422f47"), "name": "Gaogao2", "Age": 2}

>

MongoDB Basic Operations (i)