NoSQL Database Types 4가지_Day44(2)

NoSQL is an alternative to traditional SQL databases

SQL 앞에 붙은 'No' 에서 알 수 있듯이 데이터가 고정되어 있지 않은 데이터베이스 형태

 

4 popular NoSQL database

1. Key-Value Databases
2. Document Databases
3. Wide-Column Databases
4. Graph Databases

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Key-Value Database

파이썬의 dictionary 과 매우 유사

 

simplest type

Thanks to their simplicity, they are also the most scalable, allowing horizontal scaling of large amounts of data.

key-value databases do not require a predefined structure.

more flexibility, faster performance

used for caching, storing, and managing user sessions, ad servicing, and recommendations

 

 

Document Database

문서지향 데이터베이스

테이블처럼 고정된 형식의 데이터가 아닌 유동적으로 문서가 작성

consists of sets of key-value pairs stored into a document.

you can easily store data without implementing a schema

 can transfer the object model directly into a document using several different formats.

used are JSON, BSON, and XML.

Examples of NoSQL document databases include MongoDB, CouchDB, Elasticsearch, and others.

 

Wide-Column Database

각 row 에는 저마다 다른 column 이 들어가 있는 형식

가장 큰 장점 특정 칼럼에 대한 작업을 할 때

데이터가 칼럼으로 분리되어 저장이 되기 때문에 매우 빠르고 효율적

반면에 특정 레코드의 칼럼들을 전부 조회하는 작업 매우 비효율적

data is stored and grouped into separately stored columns instead of rows

wide-column databases are highly flexible

Their schema-ree characteristic allows variation of column names even within the same table,

as well as adding columns in real-time.

you can store large amounts of data within a single column

Examples of popular wide-column databases include Apache Cassandra, HBase, and CosmoDB.

 

 

Graph Database

flexible graphical representation to manage data

graphs consist of two elements :
1)Nodes (for storing data entities)
2)Edges (for storing the relationship between entities)

Nodes and edges have defined properties, and by using these properties, you can query data easily.

 it is not a commonly used NoSQL database

But social networks often use graphs to store information about how their users are linked.

OrientDB, RedisGraph, and Neo4j are just some examples of graph databases you should consider using.

 

 

출처 : phoenixnap.com/kb/nosql-database-types

NoSQL Database Types: Understanding the Differences