What are the advantages and disadvantages of PostgreSQL and MySQL?

1 Introduction

Because the company has been using PostgreSQL for a long time, it is busy with function development and does not understand some of the advantages and disadvantages of PostgreSQL. Because when developing code, mybatis cannot sense the underlying database used. Development There has been no change in the code, so there is no in-depth understanding of its underlying PostgreSQL. If I have been using mysql in the past, the basic values ​​of the underlying principles include a series of algorithms. So both postgresql and mysql are free and powerful open source databases. Many users will have a question when facing these two libraries, that is which one is the best open source database, MySQL or PostgreSQL? Which open source database should you choose?

2 Postgresql is more powerful than mysql in those aspects

● PostgreSQL adheres to SQL standards more strictly than MySQL.

● PostgreSQL handles concurrency better than MySQL:

Postgres implements multi-version concurrency control (MVCC) without read locks
Postgres supports parallelism that can use multiple CPUs/cores Query plan
Postgres can create indexes in a non-blocking manner (via CREATE INDEX CONCURRENTLY syntax), and it can create partial indexes

● PostgreSQL has better data consistency than MySQL

Mysql Comparison with Postgresql's support for programming languages

3 Why is PostgreSQL not as popular as MySQL in China

Compare the latest versions of MySQL and PostgreSQL, PostgreSQL The performance of MySQL is actually more powerful, but the reason why it is not as popular as MySQL is mainly due to historical reasons. To put it bluntly, it came out late. People who use mysql first do not rush to change.

MySQL is easier to use and can be used on Windows The platform is easy to install. In the early days, PostgreSQL did not provide a Windows platform version, and you had to compile it yourself

● It is easier to learn MySQL. It can be used out of the box and connecting as the root user is very simple, but configuring PostgreSQL, creating users, etc. are more complicated than MySQL is more complicated

●MySQL has always been endorsed by the company and has created an ecosystem of communities and supporting products. Whether it is online documentation or forums, it is richer than Postgre SQL

4 Postgresql is more important than mysql Difference

● Data type: PostgreSQL supports more data types, such as arrays, json, hstore, etc., while MySQL supports spatial data types (GIS).

● Scalability: PostgreSQL has stronger scalability than MySQL and supports custom data types, functions and stored procedures. It also provides some advanced features such as asynchronous replication, streaming replication, hot standby, etc.

PostgreSQL's ACID (Atomicity, Consistency, Isolation, and Durability) compatibility is more stringent. PostgreSQL uses a stricter isolation level by default, which ensures data consistency and integrity. MySQL uses a lower isolation level by default.

● Performance: MySQL is more suitable for large data sets than PostgreSQL because its performance is better, especially in terms of reading, writing and concurrency. PostgreSQL has better performance in handling complex queries and larger data sets.

● Open source agreement: MySQL’s open source agreement is GPL (General Public License), which means that derivative products that modify MySQL must also be released using the same agreement. The open source protocol of PostgreSQL is BSD, which means that PostgreSQL can be used by commercial software, and the modified code can be privatized.

● Cross-platform support: MySQL supports more operating systems, such as Windows, Linux, macOS, FreeBSD, etc. Although PostgreSQL supports a variety of operating systems, it was originally designed to run on UNIX operating systems.

In general, PG is more suitable for complex data structures, advanced applications and large-scale data sets, while MySQL is more suitable for simple Web applications and small-scale data sets. This is not an absolute rule, as both databases are suitable for various types of applications.

5 Comparison of postgresql features over mysql

5.1 Main features of MariaDB

MariaDB has several features that make it an excellent database, Including its wide selection of storage engines, thread pools, SQL compatibility and parallel query execution.

The following are the key points:

One of the outstanding features of MariaDB is the different storage engines to choose from. PBXT, XtraDB, Maria, and FederatedX are some of the viable engine options that can be customized as per your requirements. InnoDB is one of the general-purpose storage engines, known for its balance of high reliability and high performance.

Thread Pool: A thread pool is a collection of worker threads that effectively execute asynchronous callbacks on behalf of an application. When a request is made, MariaDB can simply acquire a previously created thread that is already in the pool. Using this scheme avoids the time required to create threads while reducing the overhead of thread cycles, resulting in faster queries and faster return of results.

SQL Compatibility: MariaDB provides support for most SQL statements, variables, definitions, and functions through client programs (such as mysqldump, mysqladmin) and plug-ins (such as audit plug-ins). JSON functions, window functions, and common table expressions (CTE) in MariaDB are also available for developers to take advantage of.

Virtual columns: Support for virtual columns is one of the main features of MariaDB and can be used to perform calculations at the database level. When multiple Apps access a column, users don't have to write separate calculations in each App; the database does this on their behalf.
Parallel Query Execution: Starting with version 10.0, you can execute multiple queries simultaneously without performance degradation, thus speeding up task execution.

5.2 The main features of PostgreSQL

In addition to being open source, PostgreSQL also has a variety of functions. Partitioning, load balancing, and connection pooling all work with PostgreSQL, giving it considerable advantages over its contemporaries.

Here is a list of some notable features of PostgreSQL:

Support for JSON data: The ability to query and store JSON enables PostgreSQL to run NoSQL workloads as well. If you are designing a database to store data from multiple sensors and you are not sure about the specific columns required to support the sensors, you can build a table with a column that follows the JSON format to store changing or unstructured data.
Powerful Extensions: PostgreSQL has an impressive feature set, including point-in-time recovery, multi-version concurrency control (MVCC), table spaces, fine-grained access control, write-ahead logging, and online/hot backups. PostgreSQL can also be case-sensitive, sorted, and formatted. It is highly scalable both in terms of the amount of data it can manage and the number of simultaneous users it can accommodate.
Data Updates: Various forms of federation, combined with replication, provide push and pull technology for almost any type of data system. These can be combined into different configurations to bridge database storage solutions without the need for ELT/ETL processing packages. The data is never moved out of the source system at all, meaning it is always up to date.
Test-driven development: PostgreSQL follows test-driven development, every bug is tested, and code is written to meet the test. These tests are integrated so the bug will not reappear in future versions of PostgreSQL. New updates to PostgreSQL will be released only when all regression test cases pass.

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