Home>Article>Database> What are relational and non-relational databases? Introduction and comparison of two common types of databases

What are relational and non-relational databases? Introduction and comparison of two common types of databases

不言
不言 forward
2019-01-17 11:13:04 6265browse

This article brings you what are relational and non-relational databases? The introduction and comparison of two common types of databases has certain reference value. Friends in need can refer to it. I hope it will be helpful to you.

Relational database:

Oracle, DB2, Microsoft SQL Server, Microsoft Access, MySQL

Non-relational database:

NoSql, Cloudant, MongoDb, redis, HBase

The difference between the two databases:

Relational database

Characteristics of relational database

1. Relational database refers to A database that usesrelational modelto organize data;

2. The biggest feature of relational database istransaction consistency;

3. Simply put, the relational model refers to thetwo-dimensional table model, and a relational database is a data organizationcomposed of two-dimensional tables and the connections between them.

Advantages of relational database

1.Easy to understand: The two-dimensional table structure is very close to the logical world Concepts, relational models are easier to understand than other models such as network and hierarchical models;
2.Easy to use: The common SQL language makes it very convenient to operate relational databases;
3.Easy to maintain: Rich integrity (entity integrity, referential integrity and user-defined integrity) greatly reduces the probability of data redundancy and data inconsistency;
4.Supports SQL, can be used for complex queries.

Disadvantages of relational database

1. The huge price paid to maintain consistency is itspoor read and write performance;
2.Fixed table structure;
3.High concurrent reading and writing requirements;
4.Highly efficient reading and writing of massive data;

Non-relational database

Features of non-relational database

1. Use thekey Value pairstores data;
2.Distributed;
3. Generallydoes not support ACIDfeatures;
4. Non-relational databases are strictly It is not a database, it should be a collection ofstructured data storagemethods.

Advantages of non-relational database

1. No need to parse through the sql layer,reading and writing performance is very high;
2. Based on key-value pairs, the data has no coupling,is easy to expand;
3. The format of storing data: the storage format of nosql is key, value form, document form, picture form, etc. Document form, picture form, etc., while relational databases only support basic types.

Disadvantages of non-relational databases

1.Does not provide sql support, and the cost of learning and using is high;
2.No transaction processing, additional functions bi and report support are not good;

The above is the detailed content of What are relational and non-relational databases? Introduction and comparison of two common types of databases. For more information, please follow other related articles on the PHP Chinese website!

Statement:
This article is reproduced at:cnblogs.com. If there is any infringement, please contact admin@php.cn delete