MySQL vs PostgreSQL? Pros and Cons

Which database to choose?

When establishing a new project, especially one on the Web, choosing a database management system is frequently an afterthought. Most frameworks include an object-relational mapping (ORM) tool that hides the differences across platforms and makes them all run at the same speed. 

Using the default choice (in most situations, MySQL) is seldom a bad idea, but it's worth thinking about. Don't get caught up in familiarity and comfort — a smart developer must constantly make educated selections based on the many possibilities, their pros, and downsides.

Database Performance

MySQL has a history of being a lightning-fast database for read-intensive workloads, often at the expense of concurrency when paired with write operations.

PostgreSQL, sometimes referred to as Postgres, bills itself as "the world's most advanced open-source relational database." It was designed to be feature-rich, extensible, and consistent with industry standards. In the past, Postgres had a more balanced performance profile: reads were slower than MySQL, but it could write massive volumes of data faster and managed concurrency better.

In recent versions, the performance disparities between MySQL and Postgres have been mostly eliminated. MySQL can still read data quickly, but only if the old MyISAM engine is used. Differences are insignificant when using InnoDB (which supports transactions, key restrictions, and other critical features) (if they even exist). 

Using the old engine is not an option since these functionalities are vital to business or consumer-scale applications. MySQL, on the other hand, has been tuned to close the gap in terms of massive data writes.

For most common applications, performance should not be a consideration when deciding between MySQL and PostgreSQL — it will be enough in both cases, even when considering predicted future expansion. Both technologies are capable of replication, and many cloud providers provide managed scaled versions of both. As a result, before you start your next project with the default database option, think about the various benefits of Postgres over MySQL.

Advantages of PostgreSQL over MySQL

MySQL is a fully relational database, whereas Postgres is an object-relational database. This implies that Postgres has capabilities such as table inheritance and function overloading, which are useful in some applications. Postgres also conforms to SQL standards more closely.

For a variety of reasons, Postgres manages concurrency better than MySQL:

Without read locks, Postgres supports Multiversion Concurrency Control (MVCC). Postgres allows query strategies that leverage many CPUs/cores in parallel. Postgres can generate non-blocking indexes (using the CREATE INDEX CONCURRENTLY syntax), as well as partial indexes (for example, if you have a model with soft deletes, you can create an index that ignores records marked as deleted) Postgres is well-known for its transaction-level data integrity protection. As a result, it is less susceptible to data corruption.

PostgreSQL vs MySQL : Installation and Extensibility

Postgres' default installation is often superior to MySQL's default installation (but you can tweak MySQL to compensate). MySQL's default settings are a little strange (for example, for character encoding and collation).

Postgres is a very extendable database. It has a variety of sophisticated data types that MySQL does not (geometric/GIS, network address types, indexed JSONB, native UUID, timezone-aware timestamps, etc.). You may even add your own data types, operators, and index types if that isn't enough.

While MySQL has experienced some license concerns, Postgres is completely open-source and community-driven. It began as a commercial product (with a free and paid version), and Oracle's acquisition of MySQL AB in 2010 has raised some developer worries about its future open-source status. However, because there are multiple open-source forks of the original MySQL (MariaDB, Percona, and so on), this is not currently seen as a significant danger.

Advantages of MySQL and when to use it

Despite all of these benefits, there are a few minor disadvantages to using Postgres that you should be aware of.

Postgres is still less popular than MySQL (despite recent gains), hence there are fewer third-party tools and database developers/administrators available.

For each new client connection, Postgres creates a new process that allocates a significant amount of RAM (about 10 MB).

Extensibility, standards compliance, scalability, and data integrity are all priorities for Postgres, often at the sacrifice of performance. Therefore, for simple, read-heavy workflows, Postgres might be a worse choice than MySQL.

Conclusion

These are just a few of the things a developer should think about while selecting a database. Furthermore, your platform provider may have a preference; for example, Heroku likes Postgres and provides operational benefits when using it. Your framework could also favor one over the other by providing superior drivers. Your employees, as always, may have an opinion!