Structured Query Language is the standard language for querying and manipulating relational databases. SQL was originally developed at IBM in the 1970s, standardized by ANSI in 1986, and has remained the dominant database query language for half a century despite repeated predictions of its replacement.
SQL's staying power comes from several sources. The relational model it was designed for turned out to match an enormous range of real-world data problems. The declarative nature of SQL queries (what you want, not how to get it) maps well to query optimizers that can exploit data statistics and index structures. The syntax is verbose but learnable by non-programmers, which has made SQL a kind of lingua franca across engineering, analytics, and business teams.
Modern SQL dialects (PostgreSQL, Snowflake, BigQuery, Databricks SQL) have extended the language substantially — JSON support, array handling, window functions, common table expressions. The 2020s have also produced non-SQL data query paradigms (GraphQL, various streaming languages) for specific use cases, but SQL remains the default for any serious data query work. AI-generated SQL has become a standard capability of LLM-powered data tools, which is making SQL accessible to a broader audience than ever before.