dbdiff vs Skeema

DBDiff is a free, MIT-licensed tool for comparing local or remote MySQL, PostgreSQL, and SQLite databases and generating migrations from schema or data differences. It can produce SQL migrations with up and down changes, using native SQL, Flyway, Liquibase, Laravel, or custom templates. The migration runner can create, apply, roll back, check, validate, repair, and baseline migrations. Listed comparison targets include tables, views, triggers, routines, types, sequences, row-level security policies, and data. Its configuration file can specify connections, drivers, diff scope, included or ignored tables and fields, and row filters. Installation options include pre-built Windows, macOS, and Linux binaries, npm, PHAR, Docker or Podman images, and Composer source. For PostgreSQL, DBDiff also compares row-level security policies and table security flags. By default, generation stops when a migration would drop a table or column, though an option permits those changes. One documented PostgreSQL limitation is that removing or reordering enum labels may leave dependent objects that prevent an automatically generated migration from applying.

Skeema is a declarative, SQL-based schema management utility for applying repository changes to MySQL and MariaDB tables and routines. It generates SQL DDL from schema files and provides diff, lint, push, and pull commands. Configurable linter rules identify unsafe changes, and Skeema verifies generated ALTER TABLE statements in a workspace before proceeding. For online schema changes, it supports database-native alterations and external tools including pt-online-schema-change and gh-ost, with execution configurable by environment and table size. Schema directories can map to multiple servers or schemas, and the utility can detect drift across shards. Listed compatibility includes MySQL 5.5–9.7, MariaDB 10.1–12.3, and Percona Server; AWS Aurora MySQL 5.7–8.4 is listed for Premium. Skeema Cloud Linter can provide automatic diff and lint output for related GitHub commits. All editions can use SSL/TLS, while Premium adds client certificates, CA verification options, and SSH tunnels. The Community plan is free at free. Plus costs $124 a month and Max costs $499 a month.