SQL
/sequel/ or /ess-cue-ell/ · noun · Development · Origin: 1974
Definitions
SQL, or Structured Query Language, is the standard language for managing and querying relational databases. Developed at IBM in the 1970s based on Edgar Codd's relational model, SQL provides a declarative syntax for defining database schemas, inserting, updating, and deleting data, and querying data using powerful operations like filtering, joining, grouping, and aggregation. Core SQL statements include SELECT for retrieving data, INSERT for adding rows, UPDATE for modifying existing data, DELETE for removing rows, and CREATE/ALTER/DROP for managing database objects like tables, indexes, and views. SQL supports transactions with ACID properties (Atomicity, Consistency, Isolation, Durability), ensuring data integrity even under concurrent access and system failures. Advanced features include subqueries, common table expressions (CTEs), window functions for analytics, stored procedures, triggers, and full-text search. SQL is supported by virtually every relational database, including PostgreSQL, MySQL, SQL Server, Oracle, and SQLite, though each has dialect-specific extensions. Despite the rise of NoSQL databases, SQL remains the most widely used database language and an essential skill for developers, data analysts, and data engineers.
In plain English: The language used to ask questions of databases and manage stored data — if data lives in a table, SQL is how you talk to it.
Example: Junior devs write SELECT * and wonder why the query takes 30 seconds — senior devs write three JOINs with covering indexes and get results in 2ms.
Origin Story
The Structured Query Language that almost had an unpronounceable name
Donald Chamberlin and Raymond Boyce at IBM designed SQL in the early 1970s, based on Edgar Codd's relational model. They originally called it **SEQUEL** (Structured English Query Language), emphasizing its English-like readability.
The name was shortened to **SQL** after IBM discovered that SEQUEL was trademarked by the Hawker Siddeley aircraft company. Whether to pronounce it "sequel" or "S-Q-L" has been debated ever since. The ANSI standard says "S-Q-L," but most people say "sequel."
SQL's declarative approach -- telling the database *what* you want, not *how* to get it -- was revolutionary. Despite decades of NoSQL movements and "SQL is dead" predictions, SQL remains the most widely used database language in the world. Even NoSQL databases eventually added SQL interfaces, leading to the joke that NoSQL means "Not Only SQL."
Coined by: Donald Chamberlin, Raymond Boyce (IBM)
Context: IBM San Jose Research Laboratory, 1970s
Fun fact: Raymond Boyce died in 1974 at age 26, just months after co-inventing SQL. The Boyce-Codd Normal Form (BCNF) in database theory is named partly in his honor. He never saw SQL become the industry standard.