web dev//SQL

SQL (Structured Query Language) is the standard language for interacting with relational databases. It is not a program or a database: it is the syntax that nearly all of them use, written over tables, columns, rows, relations (JOIN) and indexes.

SQL (Structured Query Language) is the standard language for interacting with relational databases. It is not a program or a database: it is the syntax that nearly all of them use, written over tables, columns, rows, relations (JOIN) and indexes.

Its four basic operations are the CRUD set: INSERT (create), SELECT (read), UPDATE (update) and DELETE (delete).

Schema migrations define the table structure (the schema) with CREATE TABLE and ALTER TABLE, versioned so every environment gets the same structure.

PostgreSQL, MySQL, SQLite and SQL Server each speak a dialect: the core is the same, the extras vary.