apgdiff vs Skeema

apgdiff is a free command-line tool that compares two PostgreSQL schema dump files and generates DDL statements to update an older schema or show differences. It takes an original dump and a new dump as inputs; generated SQL can be printed in the terminal or redirected to a file. The project says it can be called from batch jobs or web applications. It is written in Java and requires Java 1.6 or newer. Listed systems include Windows, Linux, Mac OS X, Solaris, and BSD, as well as other systems where Java is available. Version 2.4 is identified as the latest stable release, with binary and source ZIP downloads. Support covers selected ALTER SEQUENCE, ALTER TABLE, ALTER VIEW, COMMENT, CREATE FUNCTION, CREATE INDEX, CREATE SCHEMA, CREATE SEQUENCE, CREATE TABLE, CREATE TRIGGER, CREATE VIEW, and SET search_path statements. Other SQL statements are ignored, and an option reports ignored DDL. For CREATE TABLE column constraints, only NULL and NOT NULL are supported. The project uses the MIT License and recommends reviewing generated upgrade SQL before applying it.

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.