MongoDB series 1: the origin of NoSQL

  • 2020-05-27 07:28:23
  • OfStack

Why NoSQL?

With the development of the Internet, when we turn one server and one server into two servers, when we start to establish data backup, when we need to add a buffer layer, to adjust all the queries and invest more hardware.
Finally, you need to shard data across multiple clusters and refactor a lot of application logic to accommodate this shard. Before long, you'll find yourself constrained by the data structures you designed a few months ago.
With the rise of web2.0, the defects that cannot be overcome by the relational database itself become more and more obvious, mainly manifested as the following.
1. Requirements for high concurrent data reading and writing
2. Demand for efficient storage and access of massive data.
3. Requirements for high scalability and high availability of database.
4, database transaction 1 requirements.
5. Database realism and read-write requirements.
6. Queries for complex SQL, especially the requirements for associated queries.
NoSQL is short for Notonly SQL. NoSQL does not use SQL as the query language. Its data store can be saved without a fixed table mode, and SQL's join operation is often avoided. 1 has the characteristics of horizontal scalability.

NoSQL history?

1. The term NoSQL1 first appeared in 1998. It is a lightweight, open source, non-SQL relational database developed by Carlo Strozzi.
2. In 2009, Johan Oskarsson of Last.fm initiated a discussion on distributed open source database, and Eric Evans of Rackspace again proposed the concept of NoSQL. At this time, NoSQL mainly refers to non-relational, distributed and non-database design mode.
3. In 2009, the trend was rising, and it was defined as "non-relational" data storage. Compared with the application of relational database, this concept is undoubtedly the injection of a brand new thinking.

What's the difference between SQL and NoSql?

NoSQL has the following features
Advantages:
1. High concurrent reading and writing
2. Massive data storage
3. High scalability
4. High availability
Disadvantages:
5. Lack of transaction 1
6. Lack of real-time reading and writing
7. Complex queries are not supported

NoSQL database type

Key-value: key refers to the key-value pair of Value, usually hash table
Column database: data in the same column exists in 1
Document database: Key-Value corresponding key-value pair, Value structured data product: MongoDB
Figure structure database: take "figure" as the basic storage model, products: Neo4j, InfoGrid, InfiniteGraph

NoSQL database open source software

1. Membase software
2, Hypertable
3, ApacheCassandra
4, MongoDB

Here we use MongoDB, an introduction to MongoDB in the next article, and an example operation.


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