Reading the four families of NoSQL databases [turn]

Original address: http://database.51cto.com/art/201109/291781.htm

In the current enterprise IT architecture, system administrators and DBAs will consider using NoSQL databases to solve problems that RDBMS cannot solve, especially in the internet industry. Traditional relational databases store data in the form of tables (table) and are not able to meet the challenges of unstructured data. In the process of standardization of data, the performance of relational database suffers a bottleneck.

NoSQL, as its name implies, is Not-only SQL, which can be a good complement to relational databases. In the report before the TechTarget database, we also gave a detailed introduction to the application scenarios of NoSQL databases. NoSQL is not like a traditional relational database, its variety, and each has its advantages and disadvantages, for the DBA how to distinguish between each other is a more headache work. In this article, we'll take you through the classification of NoSQL databases and their pros and cons.

Four families of NoSQL databases

Key value (key-value) store database

This type of database primarily uses a hash table that has a specific key and a pointer to the specific data. The advantage of the Key/value model for IT systems is simplicity and ease of deployment. But if the DBA only queries or updates part of the value, Key/value becomes inefficient.

Related databases

Tokyo cabinet/tyrant, Redis, Voldemort, Berkeley DB

Typical applications

Content caching, suitable for mixing workloads and scaling large datasets

Data model

A series of key-value pairs

Advantage

Quick Query

Disadvantage

The stored data is missing a structured

Column Store Database

This part of the database is often used to deal with massive amounts of data for distributed storage. Keys still exist, but they are characterized by pointing to multiple columns. These columns are arranged by the column family.

Related databases

Cassandra, HBase, Riak

Typical applications

Distributed File Systems

Data model

To store the same column of data in a clustered type

Advantage

Find Fast, scalable, and easily distributed extensions

Disadvantage

function relative limitation

Document Type Database

The document database is inspired by Lotus Notes Office software and is similar to the first key-value store. This type of data model is a versioned document, and semi-structured documents are stored in a specific format, such as JSON. A document database can be considered an upgraded version of a key-value database, allowing for the nesting of key values. and the document database is more efficient than the key-value database query.

Related databases

CouchDB, MongoDB

Typical applications

Web Apps

Data model

A series of key-value pairs

Advantage

Data structure requirements are not strict

Disadvantage

Query performance is not high, and the lack of uniform query syntax

Graph Database (graph)

The graphical structure of the database is different from the other columns and the rigid structure of the SQL database, it is using a flexible graphical model, and can be extended to multiple servers. NoSQL databases do not have a standard query language (SQL), so database queries require a data model. Many NoSQL databases have rest-type data interfaces or query APIs.

Related databases

Neo4j, Infogrid, Infinite Graph

Typical applications

Social networks, referral systems, and more. Focus on building a relationship map

Data model

Graph structure

Strengths

Using graph structure correlation algorithm.

Weaknesses

It is necessary to calculate the whole graph to get the result, it is not easy to do the distributed cluster scheme.

Therefore, we summarize the NoSQL database in the following cases, the comparison is applicable: 1, the data model is relatively simple, 2, the need for more flexible IT systems, 3, the database performance requirements are high, 4, does not require a high degree of data consistency, 5, for a given key, more easily map complex values of the environment.

Reading the four families of NoSQL databases [turn]