MongoDB Basic Operations

1. Enter the MONGO environment

Mongo

 [[email protected] ~]# mongomongodb shell version v3.4.16connecting To:mongodb://127.0.0.1:27017mongodb Server Version:3.4.16server has startup warnings: 2018-07-20t17:53:38.109+0800 I CONTROL  [initandlisten]& nbsp;2018-07-20t17:53:38.109+0800 I Control  [initandlisten] * * warning:access CONTROL is not enabled for the Databa se.2018-07-20t17:53:38.109+0800 I CONTROL  [initandlisten] * *          read and write access To data and configuration is unrestricted.2018-07-20t17:53:38.109+0800 I CONTROL  [initandlisten]  2018-07-20t17:53:38.109+0800 I control  [initandlisten] 2018-07-20t17:53:38.109+0800 I control  [ Initandlisten] * * WARNING:/sys/kernel/mm/transparent_hugepage/enabled is ' always '. 2018-07-20t17:53:38.109+0800 I CONTROL  [initandlisten] * *        WE suggest setting it to ' Never ' 2018-07-20t17:53:38.109+0800 I CONTROL  [initandlisten] 2018-07-20t17:53:38.109+0800 I CONTROL  [initandlisten] * * WARNING:/sys/kernel/mm/transparent_hugepage/defrag is ' always '. 2018-07-20t17 : 53:38.109+0800 I CONTROL  [initandlisten] * *        WE suggest setting it to ' Never ' 2018-07-20t1 7:53:38.109+0800 I CONTROL  [initandlisten] >2. Querying all databases

Show DBS;

> Show DBS Admin 0.000GBlocal 0.000GB 3. Create or switch libraries (If the database does not exist, create the database, or switch to the specified database）

Use MyDB;

> Use mydbswitched to DB mydb> show Dbsadmin 0.000GBlocal 0.000GB

mydb Not in the list of databases, to show it, we need to   mydb The database inserts some data.

4. Create a Collection

> db.createcollection ("Log") {"OK": 1}> show dbsadmin 0.000GBlocal 0.000GBmydb 0.000GB

5. Insert data (if the collection does not exist at the time of insertion, including creating a collection and inserting data two actions) and update

> Db.logdata.insert ({name: ' Zhangsan ', Age: ' 25 '}); Writeresult ({"ninserted": 1} > Db.logdata.insert ({' _id ': ' Terrywang ', ' super_admin ': true}) Writeresult ({"Ninserte D ": 1}) > Db.logdata.find ({' _id ': ' Terrywang '}) {" _id ":" Terrywang "," Super_admin ": true} > Db.logdata.update ({' _id ': ' Terrywang '}, {$set: {' super_admin ': false}}) Writeresult ({"nmatched": 1, "nupserted": 0, "nmodified": 1}) > D B.logdata.find ({"_id": "Terrywang"}) {"_id": "Terrywang", "Super_admin": false}

6. View Collection Contents

> Db.logdata.find () {"_id": ObjectId ("5b529ef8bfde59a50f5e5397"), "name": "Lisi", "age": "{"} {"_id": "Terrywang" , "Super_admin": false}> Db.logdata.findOne ({' _id ': ' Terrywang '}) {"_id": "Terrywang", "Super_admin": true}

7. Filter by criteria

> Db.logdata.find ({"Name": "Zhangsan"}); {"_id": ObjectId ("5b529e14bfde59a50f5e5396"), "name": "Zhangsan", "Age": "25"}

Regular lookup

> Db.logdata.find ({"_id":/e*/i}) {"_id": "Terrywang", "Super_admin": false}

I indicates whether it is case-insensitive, and I is ignoring case

Filter to only one column

> Db.logdata.find ({},{d:1}) {"_id": ObjectId ("5b529ad3aea13d710cc622d5")}

8. Deleting a document

Insert a document first

> Db.logdata.insert ({name: ' Lisi ', Age: ' 30 '}); Writeresult ({"ninserted": 1}) > Db.logdata.find () {"_id": ObjectId ("5b529e14bfde59a50f5e5396"), "name": "Zhangsan" , "Age": "+"} {"_id": ObjectId ("5b529ef8bfde59a50f5e5397"), "name": "Lisi", "Age": "30"}

Delete a document

> Db.logdata.remove ({"Name": "Zhangsan"})

Writeresult ({"nremoved": 1}) > Db.logdata.find () {"_id": ObjectId ("5b529ef8bfde59a50f5e5397"), "name": "Lisi", "age ":" 30 "}

9. Display Collection

> Show Tables;loglogdata

10. Display the number of documents in the collection

> Db.logdata.find () {"_id": ObjectId ("5b529ef8bfde59a50f5e5397"), "name": "Lisi", "age": "{"} {"_id": "Terrywang" , "Super_admin": false}> Db.logdata.count () 2

11. View the collection index

> Db.logdata.getIndex () 2018-07-21t11:42:09.337+0800 E QUERY [Thread1] TypeError:db.logdata.getIndex is not a functi                        On: @ (Shell):1:1> db.logdata.getIndexes () [{"V": 2, "key": { "_id": 1}, "name": "_id_", "ns": "Mydb.logdata"}]

12. Delete a table

> Db.logdata.drop () true> show tables;logtest> Db.test.drop () true> show Tableslog

MongoDB Basic Operations