MongoDB command line basic syntax

The first is to install and configure MongoDB, this please self-Baidu, after the installation is complete, open the cmd command input MONGO. Let's start with an example, let's say that there is a class called C1, there are several people inside, people have names, age, gender and class, we operate on them separately.

　　the first step to viewing your database

Show DBS

　　The second step is to create a database　　　　

Use Ceshi

　　The third step is inserting data into the database　　

Db.test.insert ({"_id": "0", "name": "Xiaozhang", "age": +, "class": "C1", "Sex": "Woman"})

Db.test.insert ({_id: "1", Name: "Xiaoming", Age:15,class: "C1", Sex: ' Man '})

Db.test.insert ({_id: "2", Name: "Xiaowang", Age:17,class: "C1", Sex: ' Man '})

Db.test.insert ({_id: "3", Name: "Shanchu", Age:42,class: "C1", Sex: ' Man '})

Create a new test table in the testing database and insert the data note that the new database is not being inserted into the new database.

　　The fourth step updates the current test data table

　　　　Db.test.update ()

　　The fifth step shows the data table of the current data test

　　Show collections

　　Sixth step to see all the data in the table
Db.test.find ()

　　Seventh step change the age of the first piece of data

　　　　Db.test.save ({"_id": "0", "name": "Xiaozhang", Age:18,class: "C1", Sex: "Man"})

If the change succeeds there will be Writeresult ({"nmatched": 1, "nupserted": 0, "nmodified": 1}) Note:the "_id" inside the save is to be matched, if not specified, a new data insert is generated. To the data table, in fact, this method is to delete the data after the new insert, if you just want to change the field name of a property, then you need to write these other properties are complete, otherwise there will only be a field name is inserted, the other field names are all deleted!!!

At this point you can use Db.test.find () to view the current data

　　Eighth Step Delete fourth data

　　　　Db.test.remove ({"Name": "Shanchu"}) uses Db.test.find () to view the current data

　　Nineth step to find matching items

Db.test.find ({"Age": {$gt: +}}) "$lt", "$lte", "$gt", "$gte" correspond to <,<=,>,>=

At this point, you can see data that's older than 17.

　　Step Tenth Delete the entire data sheet

　　　　Db.test.drop () Use show collections to see if the test table exists

　　Step 11th Delete the database　

First use test to create a table and insert a piece of data, you can refer to the above method, using Db.dropdatabase () delete the current database, delete after the library using show DBS to see if the database was deleted successfully

To this MongoDB some basic syntax has been introduced, more content please look forward to the next update.

　　

　　

　　

　　

MongoDB command line basic syntax