SQL Sublanguages Explained: DDL, DML, DQL, DCL and TCL With a Supermarket Example

This DEV Community article explains the five SQL sublanguages, which group commands by the kind of database operation they perform. It uses a fictional supermarket, Sunrise Supermarket, as a running example for covering each group. The author describes DDL for defining and modifying database structures and touches on related operations such as recording sales and controlling access. The piece walks through practical commands including CREATE TABLE, ALTER TABLE, DROP TABLE, TRUNCATE TABLE and CREATE INDEX.