SQL: 'Sequel' or 'S-Q-L'? Both Are Correct — Here's the Full Story
SQL can be correctly pronounced either as "sequel" (/ˈsiːkwəl/) or spelled out as "S-Q-L" (/ˌɛsˌkjuːˈɛl/) — both are accepted. The ISO standard says "S-Q-L", but IBM's original language was called "SEQUEL", and many database communities (especially Oracle and SQL Server) still prefer "sequel." Walk into any dev team meeting and you'll hear both. Understanding this split teaches you something important about how tech language evolves.
IBM's original: "SEQUEL"
SQL started as SEQUEL (Structured English Query Language) at IBM in the 1970s. For years, everyone called it "SEQUEL." The name made sense — it was literally spelled out in the acronym.
Then IBM got a trademark issue. There was already a software product called SEQUEL, so IBM renamed their language to SQL (Structured Query Language) in 1980. But even after the rename, many IBM engineers and veterans continued calling it "sequel" — the pronunciation habit stuck.
Today, saying "sequel" is historically accurate and widely accepted, especially among experienced developers. It's the direct descendant of the original SEQUEL name.
Oracle's adoption: "Sequel" becomes standard
When Oracle popularized SQL through their commercial database system, they leaned into the "sequel" pronunciation. Oracle's official documentation, training materials, and engineers all used "sequel." This gave the soft pronunciation serious institutional backing.
Because of Oracle's dominance in enterprise databases throughout the 1980s and 1990s, "sequel" became the most common pronunciation in corporate and database-focused development circles. To this day, database administrators often prefer "sequel."
The spelling-it-out alternative
Some developers — particularly those who work primarily with open-source databases like PostgreSQL or MySQL — spell it out: "S-Q-L." This pronunciation became more common as databases democratized and new generations of developers learned SQL without the IBM/Oracle historical context.
Saying "S-Q-L" also avoids the awkwardness of calling different SQL databases by inconsistent names. You'd say PostgreSQL (spelled out, not "post-sequel"), MySQL (spelled out), and SQL (sometimes spelled out for consistency).
Which should you use?
Both are correct and widely used. Here's a practical guide:
- "Sequel": Perfectly appropriate, historically grounded, and still preferred in enterprise/Oracle-heavy environments.
- "S-Q-L": Growing in popularity, especially in open-source and cloud-native communities. Less ambiguous, more modern.
Pick whichever feels natural to your work environment. In any dev team, people will understand you. The key is consistency within your own speech.
Master SQL and database terminology
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