MongoDB startup and underlying commands

1. Parameter Start MongoDB
./mongod--dbpath=/usr/local/mongo/mongodb/data--fork--logpath=/usr/local/mongo/mongodb/logs--nohttpinterface


2./mongo Connection MongoDB


3. Connect MongoDB database with Ruby


Installing Ruby and RubyGems


Configuring CONNECT.RB Files


Enter command: Ruby CONNECT.RB run Connection




4. Order
General MONGO New
Db.users.insert ({name: "Jony"})


General MONGO Modification
Db.users.update ({name: "Jony"},{$set: {country: "Fujian"}})
If there is no conutry field in the Users collection, it is equivalent to adding the Country field, if it exists, modify


Db.users.update ({name: "Jony"},{country: "Fujian"})
If there is no $set, the name field is deleted directly and replaced with the Country field


Common MONGO Search
Db.users.find () or Db.users.find ({name: "Jony"},{country: "Fujian"})


It command
Show next set of information


Create a large collection
for (i=0;i<20000;i++) {
Db.numbers.save ({num:i});
}
Create an index
Db.numbers.createIndex ({num:1})
View Index
Db.numbers.getIndexes ()




displaying database information
Show DBS


Show all collection Information
Show collections


View collection Status
Db.stats () or db.numbers.stats ()
















Ruby Connection MONGO Command


Query Collection
$users. Find (). |user| Put user end
The above statement means
Iterate the data in the Users collection into user output


Modify
$users. Find ({"name" => "Jony"}). Update_One ({"$set" =>{"City" => "Fuzhou"})


Delete


$users. Find ({"name" => "Jony"}). Delete_one deletes the first matching
$users. Find ({"name" => "Jony"}). Delete_many Delete all matching


Users.drop Delete all collections