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SQL is 50 years old: why it is still essential

In computer science, some tools disappear after a few years. Technologies change quickly, new languages appear, and new solutions sometimes replace older ones. And yet, SQL is still here!

Created in the 1970s, SQL is still used every day by millions of developers, from small applications to critical systems.

You might think that a language this old would have been replaced a long time ago. But SQL has a particular strength: it solves a fundamental problem that has not changed:

How can we store, organize, and efficiently query data?

SQL stands for Structured Query Language. Its history began in the 1970s at IBM with the work around the relational model proposed by Edgar F. Codd.

The idea was different from the approaches used at the time: instead of storing data as complex structures tightly dependent on the program, data is organized into tables connected to each other.

A table contains rows representing records, columns representing properties and relationships connecting different pieces of information.

Example:

CREATE TABLE users (
    id INT PRIMARY KEY,
    name VARCHAR(100),
    email VARCHAR(255)
);

This approach completely changed the way data was managed. We do not always realize it today.

Why has SQL survived for so long?

Because the data problem never disappears

Frameworks change. Languages evolve. Architectures transform.

But almost every application needs to manage data: users, orders, payments, statistics etc.

SQL remains an effective way to interact with this data. Even an application written in a recent language often ends up communicating with an SQL database.

A language easy to understand, difficult to master

One of SQL's strengths is its apparent simplicity. A basic query is easy to read:

SELECT name
FROM users
WHERE id = 10;

Even a non-developer can understand the intention. And for a developer, it is immediately understandable even without SQL knowledge.

But SQL quickly becomes more complex with:

  • joins;
  • indexes;
  • transactions;
  • execution plans.

It is a language that is easy to start with, but difficult to completely master.

SQL databases have evolved a lot

Saying that SQL is old does not mean that it has remained frozen.

SQL has continued to evolve over the years, and many features have been added:

  • advanced indexes;
  • replication;
  • partitioning;
  • JSON functions (this evolution really changed my life...);
  • full-text search;
  • stored procedures;
  • data analysis.

Databases such as PostgreSQL or MySQL are very different from their first versions.

The language has aged, but the ecosystem has continued to evolve and adapt to new needs.

The relational model still meets many needs

NoSQL databases have gained a lot of popularity in recent years (I have to admit, I have used them very little so far). They are very useful in some cases where they can be more relevant than SQL databases:

  • very large volumes of data;
  • variable structures;
  • specific performance requirements.

But many applications need strong guarantees:

  • data consistency;
  • transactions;
  • complex relationships.

For example, an e-commerce order often involves several operations:

1. create an order
2. remove a product from inventory
3. record a payment
4. generate an invoice

We do not want to end up with a paid order but without a registered product. SQL transactions are designed exactly for this type of problem.

Developers already know SQL

A technology has a huge advantage when it benefits from decades of collective experience.

SQL benefits from many tools, extensive documentation, proven solutions, and especially experienced developers who have been working with it for decades. Personally, I have already been using it for more than 20 years... Back then, I did not have any gray hair.

A company choosing SQL today is not depending on a tool that appeared two years ago, and its developers probably already know SQL.

SQL's weaknesses still exist

Unfortunately, SQL is not perfect.

It can become difficult to manage with very large databases. Even with partitioning, things are not always simple or obvious.

You can quickly end up with complex SQL queries that become difficult to maintain. You can also make poor choices when designing the data model.

And I will not even talk about indexes...

SQL requires a real understanding of data and how the database engine works. Otherwise, you can quickly get some unpleasant surprises.

Why will SQL still be used in the future?

I think SQL will remain present for a long time, not because it is old, but because it solves a universal problem. Technologies change, but applications will always need to store information while guaranteeing consistency, quickly retrieve data and perform complex operations.

SQL may no longer be the only possible choice, but it remains one of the best tools for many problems.

Conclusion

SQL has gone through several generations of computing. It has experienced desktop applications, the web, mobile, the cloud, and now artificial intelligence.

Few technologies can claim such longevity!

Alright, I am going back to writing a little SQL query...

cyrilou