303. Mongo Shell Bacis

SQL Database와 NoSQL의 차이점은 아래의 table과 같지만 가장 중요한 점은 데이터 저장 방법이 table 형태인지, JSON type "Key-Value" 형태인지 여부이다.

 

Differences between SQL and NoSQL

The table below summarizes the main differences between SQL and NoSQL databases.

SQL DatabasesNoSQL Databases

Data Storage Model	Tables with fixed rows and columns	Document: JSON documents, Key-value: key-value pairs, Wide-column: tables with rows and dynamic columns, Graph: nodes and edges
Development History	Developed in the 1970s with a focus on reducing data duplication	Developed in the late 2000s with a focus on scaling and allowing for rapid application change driven by agile and DevOps practices.
Examples	Oracle, MySQL, Microsoft SQL Server, and PostgreSQL	Document: MongoDB and CouchDB, Key-value: Redis and DynamoDB, Wide-column: Cassandra and HBase, Graph: Neo4j and Amazon Neptune
Primary Purpose	General purpose	Document: general purpose, Key-value: large amounts of data with simple lookup queries, Wide-column: large amounts of data with predictable query patterns, Graph: analyzing and traversing relationships between connected data
Schemas	Rigid	Flexible
Scaling	Vertical (scale-up with a larger server)	Horizontal (scale-out across commodity servers)
Multi-Record ACID Transactions	Supported	Most do not support multi-record ACID transactions. However, some—like MongoDB—do.
Joins	Typically required	Typically not required
Data to Object Mapping	Requires ORM (object-relational mapping)	Many do not require ORMs. MongoDB documents map directly to data structures in most popular programming languages.

 

Mongo start Commands

	Start command	Termination command
Server	#mongod	Ctrl + c
Shell	#mongo	Ctrol + c

 

Mongo Shell CRUD Commands(생성, 조회, 업데이트, 삭제)

Shell Commands	Remark
db.foods.insert({name: "Kimchi", "origin: "Korea", isFav: true})	foods에 name과 origin, isFav이란 Key에 해당하는 value들을 각각 저장
db.foods.find()	foods에 저장된 모든 값들을 출력한다
db.foods.find({name: "sushi"})	foods에 저장된 데이터 중 Key-Value가 각각 name, sushi인 데이터를 모두 보여준다.
db.foods.update({name: "Kimch"}, {name: "Bulgogi"})	name이 Kimch인 데이터를 {name: "Bulgogi"}라는 값으로 update한다. 기존의 3개 Key-Value가 사라지고, 오직 name: Bulgogi라는 1개의 Key-Value 값만 저장된다.
db.foods.update({name: "Kimch"}, {$set: {name: "Bulgogi"}})	name이 Kimch인 데이터에서 name만 Bugogi로 업데이트한다
db.foods.remove({name: "Bulgogi"})	name이 "Bulgogi"인 데이터를 모두 삭제한다.