The difference between relational and non-relational databases

Ref: 53896702

The current mainstream relational databases are Oracle, DB2, Microsoft SQL Server, Microsoft Access, MySQL, and more.

Non-relational databases have NOSQL, Cloudant

NoSQL and relational database comparisons?
Advantages:
1) Cost: NoSQL databases are simple and easy to deploy, basically open source software, and do not need to spend a lot of money to buy using Oracle, compared to the relational database is cheaper than the price.
2) query speed: NoSQL database stores data in cache, relational database stores data on hard disk, natural query speed is far less than NoSQL database.
3) format for storing data: NoSQL storage formats are key,value forms, document forms, picture forms, and so on, so you can store the underlying types and objects or collections , and the database supports only the underlying types.
4) Extensibility: The limitations of a relational database with a multi-table query mechanism like join cause the extension to be difficult.
Disadvantages:
1) Maintenance of tools and information is limited, because NoSQL is a new technology, not with the relational database 10几 years of technology in the same breath.
2) does not provide support for SQL, if it does not support industry standards such as SQL, will generate a certain user's learning and use costs.

3) does not provide a relational database to deal with things.

Benefits of non-relational databases: 1. Performance NoSQL is based on key-value pairs, and can be imagined as the corresponding relationship between the primary key and the value in the table, and does not need to be parsed by the SQL layer, so the performance is very high. 2. Extensibility is also due to the fact that there is no coupling between data based on key-value pairs, so it is easy to scale horizontally .

Benefits of Relational databases: 1. Complex queries can easily use SQL statements to make very complex data queries between a table and multiple tables. 2. Transactional support enables data access requirements with high security performance. For these two types of databases, the other's advantage is their own weakness, and vice versa.

The benefits of a relational database:

1. Maintain data consistency (transaction processing)

2. Due to standardization, the cost of updating data is small (the same fields are basically only one place)

3. Complex queries such as joins can be made

One of the best advantages of relational databases is the ability to maintain data consistency.

The lack of a relational database:

Not good at handling

1. Write processing of large amounts of data

2. Index or table structure (schema) changes for tables with data updates

3. Apply when field is not fixed

4. Handling of Quick return results for simple queries

The difference between relational and non-relational databases