In Ruby on Rails, the configuration option config.active_record.schema_format determines the format for dumping the database schema. It can be set to either :ruby (using Ruby DSL) or :sql (using plain SQL). While :ruby is the default and works well for many applications, there are compelling reasons to consider :sql, particularly in more complex setups.
Understanding the Differences
:ruby Format:
- Uses Ruby DSL to generate schema.rb.
- Is database-agnostic, making it suitable for simpler applications or when switching between different DBMS (Database Management Systems).
:sql Format:
- Generates structure.sql using raw SQL statements.
- Captures all database-specific elements like triggers, views, stored procedures, and complex indexes.
Advantages of :sql Format
- Database Specific Features:
If your application uses database-specific features like foreign key constraints, advanced indexing, triggers, or stored procedures, :sql ensures these are accurately captured in the schema file. The Ruby DSL used in schema.rb can’t always express these complex database features. - Complex Indexes…