sqldef

What sqldef is

sqldef is a command-line tool for comparing SQL schemas and managing relational database migrations with standard SQL DDLs. Users describe the intended schema in SQL; sqldef compares that definition with the current database and generates and applies the changes needed to match. The project lists support for MySQL, MariaDB, TiDB, PostgreSQL, SQL Server, and SQLite3. Operations are described as idempotent, so they can be run repeatedly. A dry-run mode previews changes without applying them, while offline mode compares SQL files without a database connection, including for validation and migration-script generation. An annotation can identify renamed tables, columns, indexes, and ENUM values. The project supplies single-binary executables and Docker images, and a GitHub Action can preview schema changes. An online browser demo uses a WebAssembly build to compare schemas and generate DDLs. sqldef is open source: source files use the MIT License, except for the parser, which uses Apache License 2.0. Debian packages are not currently available; Linux users are directed to binaries or Docker images.