foreword
This article belongs to the column "Theoretical System of Big Data". This column is original by the author. Please indicate the source for the citation. Please point out the shortcomings and mistakes in the comment area, thank you!
For the directory structure and references of this column, please refer to the Big Data Theory System
mind Mapping
OldSQL
OldSQL is a term often used in contrast to NoSQL databases to refer to traditional SQL (Structured Query Language) databases. A traditional SQL database is a relational model-based database that uses tables and predefined schemas to store and manage data. Traditional SQL databases have powerful transaction support, complex query capabilities, and rich data integrity constraints .
In contrast, NoSQL databases adopt a non-relational model and do not use fixed tables and predefined schemas. NoSQL databases are more flexible, suitable for large-scale distributed data storage and processing, and show better performance and scalability in some application scenarios.
Therefore, the concept of OldSQL is often used to emphasize the difference between traditional SQL databases and NoSQL databases, especially in dealing with big data, high concurrency and distributed environments.
NoSQL
About NoSQL, please refer to my blog - what is NoSQL?
NewSQL
NewSQL is a term used to describe a new class of database systems that combines traditional SQL databases and NoSQL databases. NewSQL database is designed to provide strict data consistency and complex query capabilities of traditional SQL databases, while having scalability, high performance and distributed processing capabilities of NoSQL databases.
NewSQL database is designed to solve the challenges encountered by traditional SQL databases in large-scale and high-concurrency environments, such as processing massive data, highly concurrent transactions, and distributed deployment. These database systems typically employ a distributed architecture that can scale horizontally to provide better performance and fault tolerance.
Unlike NoSQL databases, NewSQL databases retain the relational model, transaction support, and SQL query language of traditional SQL databases, which makes them more suitable for application scenarios that require complex queries, strict data consistency, and data integrity, such as finance, e-commerce, and enterprise resource management systems.
In short, NewSQL is a new type of database system, which combines the advantages of traditional SQL databases and NoSQL databases, and aims to provide database solutions with high performance, scalability and complex query capabilities.
OLTP/OLAP
In the development of OldSQL, NoSQL and NewSQL, there is a concept that has always existed, that is, OLTP (Online Transaction Processing) and OLAP (Online Analytical Processing).
About OLTP and OLAP, please refer to my blog - the difference between OLTP and OLAP?
OldSQL 实际上可以视为 OLTP 的一种实现，NoSQL 可以看作是 OLAP 的一种实现，而 NewSQL 则是将 OLTP 和 OLAP 结合起来的实现。
Summarize
At the beginning of the birth of relational database (RDBMS), SQL (Structured Query Language) was mainly used for data manipulation and query, so this stage is called OldSQL. RDBMS organizes data in the form of tables, and the tables are related by foreign keys.
With the development of the Internet, the amount and type of data continue to increase, and the requirements for data processing are also becoming higher and higher. The table structure of RDBMS cannot handle unstructured data well, nor can it cope with the storage and query of large-scale data , so NoSQL technology came into being.
NoSQL refers to "non-relational database". Instead of using table structure to store data, it uses key-value pairs, documents, column families, etc. to store data, which can better handle unstructured data and large-scale data. In addition, NoSQL also supports distributed storage and horizontal expansion, which can well meet the needs of Internet applications.
With the widespread application of NoSQL, some problems have also begun to appear, such as lack of transaction support, complex queries and so on. In order to take into account the advantages of NoSQL and RDBMS, NewSQL technology came into being.
NewSQL combines the distributed and high-performance features of NoSQL with the transaction and complex query features of RDBMS. The goal of NewSQL technology is to provide distributed, high-performance relational database solutions, so that relational databases can also adapt to the needs of large-scale data processing and high concurrent access.
In general, from OldSQL to NoSQL and then to NewSQL, it is the continuous evolution of database technology adapting to the Internet era, the continuous innovation of technology and the continuous change of application scenarios.