Rails 7 adds support for setting the schema dump filepath in the database config

One of the best features of Rails is its ORM,
Active Record which makes it easy to interface
with various database engines
and even multiple databases themselves.
However, not every database-specific
task was available to these shards.

Only in Rails 6 was additional database-specific rake tasks
for multi-database users added.
This allowed tasks like schema dumps
to be run on individual databases via rails db:schema:dump:primary
and more.

Before

However, doing this will not allow users to specify
the schema dump filepath.
All dumps will write to the same location.
This was quite troublesome as there was no easy way
to quickly dump all shards without manual intervention.

After

Fortunately, this PR
allows users to set the filename of the schema
or structure dump in the database config.

  production:
    primary:
      database: my_db
      schema_dump: my_schema_dump_filename.rb
    animals:
      database: animals_db
      schema_dump: false

The filename set in schema_dump will be used by the application.
It is also possible to toggle dumping itself
by setting schema_dump to false.