I Google this info about every 48hours, so I figure it’s time I made it closer to my fingertips. This post is not original. I am blatantly coping from here.

In the order I use them:

Basic migration functions

• create_table(name, options)
• drop_table(name)
• rename_table(old_name, new_name)
• add_column(table_name, column_name, type, options)
• rename_column(table_name, column_name, new_column_name)
• change_column(table_name, column_name, type, options)
• remove_column(table_name, column_name)
• add_index(table_name, column_name, index_type)
• remove_index(table_name, column_name)

Commands I commonly use:

• rake migrate RAILS_ENV=”production”: run on production server after deploying project
• rake db_schema_dump: run after you create a model to capture the schema.rb
• rake db_schema_import: import the schema file into the current database (on error, check if your schema.rb has ”:force => true” on the create table statements
• ./script/generate migration MigrationName: generate a new migration with a new ‘highest’ version (run ’./script/generate migration’ for this info at your fingertips)
• rake migrate: migrate your current database to the most recent version
• rake migrate VERSION=5: migrate your current database to a specific version (in this case, version 5)