Introduction to the advantages and disadvantages of Relational Database and NOSQL Database

Relational database:

1) the characteristics of relational database are:

-the data relational model is based on relational models, structured storage, and integrity constraints.

-based on two-dimensional tables and their relationships, data operations such as join, union, intersection, difference, division and so on are required.

-use structured query language (SQL) to read and write data.

Operations require data consistency, transactions and even strong consistency.

2) advantages:

-maintain data consistency (transaction processing)

-complex queries such as join can be performed.

-generalization and mature technology.

3) disadvantages:

-data reading and writing must be parsed by sql, and the performance of reading and writing for large amounts of data and high concurrency is insufficient.

-Lock is required when reading and writing data or modifying data structure, which affects concurrent operations.

-unable to adapt to unstructured storage.

It is difficult to expand.

-expensive and complicated.

NoSQL database:

1) the characteristics of NoSQL database are:

-unstructured storage.

-based on multidimensional relational model.

-has a unique usage scenario.

2) advantages:

-High concurrency, big data has strong reading and writing ability.

-basically supports distribution, easy to expand, and scalable.

-simple, weakly structured storage.

3) disadvantages:

-join and other complex operation ability is weak.

-transaction support is weak.

-poor versatility.

-complex business scenarios without complete constraints are poorly supported.