I have an application that requires a sequence to be present in the database. I have a migration that does the following:
class CreateSequence < ActiveRecord::Migration
def self.up
execute "CREATE SEQUENCE sequence"
end
def self.down
execute "DROP SEQUENCE sequence"
end
end
This does not modify the schema.rb
and thus breaks rake db:setup
. How can I force the schema to include the sequence?
Note: The sequence exists after running rake db:migrate
.
Rails Migrations because they aim toward a schema of tables and fields, instead of a complete database representation including stored procedures, functions, seed data.
When you run rake db:setup, this will create the db, load the schema and then load the seed data.
A few solutions for you to consider:
Choice 1: create your own rake task that does these migrations independent of the Rails Migration up/down. Rails Migrations are just normal classes, and you can make use of them however you like. For example:
rake db:create_sequence
Choice 2: run your specific migration after you load the schema like this:
rake db:setup
rake db:migrate:up VERSION=20080906120000
Choice 3: create your sequence as seed data, because it's essentially providing data (rather than altering the schema).
db/seeds.rb
Choice 4 and my personal preference: run the migrations up to a known good point, including your sequence, and save that blank database. Change rake db:setup to clone that blank database. This is a bit trickier and it sacrifices some capabilities - having all migrations be reversible, having migrations work on top of multiple database vendors, etc. In my experience these are fine tradeoffs. For example:
rake db:fresh #=> clones the blank database, which you store in version control
All the above suggestions are good. however, I think I found a better solution. basically in your development.rb put
config.active_record.schema_format = :sql
For more info see my answer to this issue - rake test not copying development postgres db with sequences
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With