SQL (Structured Query Language) is a language made for working with relational databases. It was created in the early 1970s at IBM by Donald D. Chamberlin and Raymond F. Boyce. The original name was SEQUEL, which stood for “Structured English Query Language,” but it was later shortened to SQL because of a trademark issue.
This page is the main place for all SQL topics. Here you will find simple guides, real examples, and short notes from problems I solved while working with different SQL engines. In the future, this section will also include sub‑topics like PostgreSQL, MySQL, SQL Server, SQLite, and even key‑value stores like Redis and LMDB.
The goal is to explain SQL clearly and practically, without noise, and with examples you can use right away.
If you want to read more about the history of SQL, here are two good starting points:
- Wikipedia — SQL history (general, detailed, neutral)
- IBM — System R and the origins of SQL (background on the IBM research that led to SQL)
- SQL – Balancing Performance and ManagementSQL - Balancing Performance and Management using Table partitioning d a large database table into...