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Diffstat (limited to 'guides/source/active_record_migrations.md')
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diff --git a/guides/source/active_record_migrations.md b/guides/source/active_record_migrations.md index 9d33de5fa2..12805f012c 100644 --- a/guides/source/active_record_migrations.md +++ b/guides/source/active_record_migrations.md @@ -12,7 +12,7 @@ After reading this guide, you will know: * The generators you can use to create them. * The methods Active Record provides to manipulate your database. -* The bin/rails tasks that manipulate migrations and your schema. +* The rails tasks that manipulate migrations and your schema. * How migrations relate to `schema.rb`. -------------------------------------------------------------------------------- @@ -123,7 +123,7 @@ Of course, calculating timestamps is no fun, so Active Record provides a generator to handle making it for you: ```bash -$ bin/rails generate migration AddPartNumberToProducts +$ rails generate migration AddPartNumberToProducts ``` This will create an empty but appropriately named migration: @@ -140,7 +140,7 @@ followed by a list of column names and types then a migration containing the appropriate `add_column` and `remove_column` statements will be created. ```bash -$ bin/rails generate migration AddPartNumberToProducts part_number:string +$ rails generate migration AddPartNumberToProducts part_number:string ``` will generate @@ -156,7 +156,7 @@ end If you'd like to add an index on the new column, you can do that as well: ```bash -$ bin/rails generate migration AddPartNumberToProducts part_number:string:index +$ rails generate migration AddPartNumberToProducts part_number:string:index ``` will generate @@ -174,7 +174,7 @@ end Similarly, you can generate a migration to remove a column from the command line: ```bash -$ bin/rails generate migration RemovePartNumberFromProducts part_number:string +$ rails generate migration RemovePartNumberFromProducts part_number:string ``` generates @@ -190,7 +190,7 @@ end You are not limited to one magically generated column. For example: ```bash -$ bin/rails generate migration AddDetailsToProducts part_number:string price:decimal +$ rails generate migration AddDetailsToProducts part_number:string price:decimal ``` generates @@ -209,7 +209,7 @@ followed by a list of column names and types then a migration creating the table XXX with the columns listed will be generated. For example: ```bash -$ bin/rails generate migration CreateProducts name:string part_number:string +$ rails generate migration CreateProducts name:string part_number:string ``` generates @@ -233,7 +233,7 @@ Also, the generator accepts column type as `references` (also available as `belongs_to`). For instance: ```bash -$ bin/rails generate migration AddUserRefToProducts user:references +$ rails generate migration AddUserRefToProducts user:references ``` generates @@ -252,7 +252,7 @@ For more `add_reference` options, visit the [API documentation](http://api.rubyo There is also a generator which will produce join tables if `JoinTable` is part of the name: ```bash -$ bin/rails g migration CreateJoinTableCustomerProduct customer product +$ rails g migration CreateJoinTableCustomerProduct customer product ``` will produce the following migration: @@ -276,7 +276,7 @@ relevant table. If you tell Rails what columns you want, then statements for adding these columns will also be created. For example, running: ```bash -$ bin/rails generate model Product name:string description:text +$ rails generate model Product name:string description:text ``` will create a migration that looks like this @@ -304,7 +304,7 @@ the command line. They are enclosed by curly braces and follow the field type: For instance, running: ```bash -$ bin/rails generate migration AddDetailsToProducts 'price:decimal{5,2}' supplier:references{polymorphic} +$ rails generate migration AddDetailsToProducts 'price:decimal{5,2}' supplier:references{polymorphic} ``` will produce a migration that looks like this @@ -727,9 +727,9 @@ you will have to use `structure.sql` as dump method. See Running Migrations ------------------ -Rails provides a set of bin/rails tasks to run certain sets of migrations. +Rails provides a set of rails tasks to run certain sets of migrations. -The very first migration related bin/rails task you will use will probably be +The very first migration related rails task you will use will probably be `rails db:migrate`. In its most basic form it just runs the `change` or `up` method for all the migrations that have not yet been run. If there are no such migrations, it exits. It will run these migrations in order based @@ -744,7 +744,7 @@ is the numerical prefix on the migration's filename. For example, to migrate to version 20080906120000 run: ```bash -$ bin/rails db:migrate VERSION=20080906120000 +$ rails db:migrate VERSION=20080906120000 ``` If version 20080906120000 is greater than the current version (i.e., it is @@ -761,7 +761,7 @@ mistake in it and wish to correct it. Rather than tracking down the version number associated with the previous migration you can run: ```bash -$ bin/rails db:rollback +$ rails db:rollback ``` This will rollback the latest migration, either by reverting the `change` @@ -769,7 +769,7 @@ method or by running the `down` method. If you need to undo several migrations you can provide a `STEP` parameter: ```bash -$ bin/rails db:rollback STEP=3 +$ rails db:rollback STEP=3 ``` will revert the last 3 migrations. @@ -779,10 +779,10 @@ back up again. As with the `db:rollback` task, you can use the `STEP` parameter if you need to go more than one version back, for example: ```bash -$ bin/rails db:migrate:redo STEP=3 +$ rails db:migrate:redo STEP=3 ``` -Neither of these bin/rails tasks do anything you could not do with `db:migrate`. They +Neither of these rails tasks do anything you could not do with `db:migrate`. They are simply more convenient, since you do not need to explicitly specify the version to migrate to. @@ -809,7 +809,7 @@ the corresponding migration will have its `change`, `up` or `down` method invoked, for example: ```bash -$ bin/rails db:migrate:up VERSION=20080906120000 +$ rails db:migrate:up VERSION=20080906120000 ``` will run the 20080906120000 migration by running the `change` method (or the @@ -819,13 +819,13 @@ Active Record believes that it has already been run. ### Running Migrations in Different Environments -By default running `bin/rails db:migrate` will run in the `development` environment. +By default running `rails db:migrate` will run in the `development` environment. To run migrations against another environment you can specify it using the `RAILS_ENV` environment variable while running the command. For example to run migrations against the `test` environment you could run: ```bash -$ bin/rails db:migrate RAILS_ENV=test +$ rails db:migrate RAILS_ENV=test ``` ### Changing the Output of Running Migrations @@ -896,7 +896,7 @@ Occasionally you will make a mistake when writing a migration. If you have already run the migration, then you cannot just edit the migration and run the migration again: Rails thinks it has already run the migration and so will do nothing when you run `rails db:migrate`. You must rollback the migration (for -example with `bin/rails db:rollback`), edit your migration, and then run +example with `rails db:rollback`), edit your migration, and then run `rails db:migrate` to run the corrected version. In general, editing existing migrations is not a good idea. You will be |