diff options
Diffstat (limited to 'activerecord/lib')
| -rw-r--r-- | activerecord/lib/active_record/migration.rb | 66 |
1 files changed, 51 insertions, 15 deletions
diff --git a/activerecord/lib/active_record/migration.rb b/activerecord/lib/active_record/migration.rb index 90b8a29869..c8b96b8de0 100644 --- a/activerecord/lib/active_record/migration.rb +++ b/activerecord/lib/active_record/migration.rb @@ -194,17 +194,18 @@ module ActiveRecord # # == Available transformations # + # === Creation + # + # * <tt>create_join_table(table_1, table_2, options)</tt>: Creates a join + # table having its name as the lexical order of the first two + # arguments. See + # ActiveRecord::ConnectionAdapters::SchemaStatements#create_join_table for + # details. # * <tt>create_table(name, options)</tt>: Creates a table called +name+ and # makes the table object available to a block that can then add columns to it, # following the same format as +add_column+. See example above. The options hash # is for fragments like "DEFAULT CHARSET=UTF-8" that are appended to the create # table definition. - # * <tt>drop_table(name)</tt>: Drops the table called +name+. - # * <tt>change_table(name, options)</tt>: Allows to make column alterations to - # the table called +name+. It makes the table object available to a block that - # can then add/remove columns, indexes or foreign keys to it. - # * <tt>rename_table(old_name, new_name)</tt>: Renames the table called +old_name+ - # to +new_name+. # * <tt>add_column(table_name, column_name, type, options)</tt>: Adds a new column # to the table called +table_name+ # named +column_name+ specified to be one of the following types: @@ -215,24 +216,59 @@ module ActiveRecord # Other options include <tt>:limit</tt> and <tt>:null</tt> (e.g. # <tt>{ limit: 50, null: false }</tt>) -- see # ActiveRecord::ConnectionAdapters::TableDefinition#column for details. - # * <tt>rename_column(table_name, column_name, new_column_name)</tt>: Renames - # a column but keeps the type and content. - # * <tt>change_column(table_name, column_name, type, options)</tt>: Changes - # the column to a different type using the same parameters as add_column. - # * <tt>remove_column(table_name, column_name, type, options)</tt>: Removes the column - # named +column_name+ from the table called +table_name+. + # * <tt>add_foreign_key(from_table, to_table, options)</tt>: Adds a new + # foreign key. +from_table+ is the table with the key column, +to_table+ contains + # the referenced primary key. # * <tt>add_index(table_name, column_names, options)</tt>: Adds a new index # with the name of the column. Other options include # <tt>:name</tt>, <tt>:unique</tt> (e.g. # <tt>{ name: 'users_name_index', unique: true }</tt>) and <tt>:order</tt> # (e.g. <tt>{ order: { name: :desc } }</tt>). + # * <tt>add_reference(:table_name, :reference_name)</tt>: Adds a new column + # +reference_name_id+ by default an integer. See + # ActiveRecord::ConnectionAdapters::SchemaStatements#add_reference for details. + # * <tt>add_timestamps(table_name, options)</tt>: Adds timestamps (+created_at+ + # and +updated_at+) columns to +table_name+. + # + # === Modification + # + # * <tt>change_column(table_name, column_name, type, options)</tt>: Changes + # the column to a different type using the same parameters as add_column. + # * <tt>change_column_default(table_name, column_name, default)</tt>: Sets a + # default value for +column_name+ definded by +default+ on +table_name+. + # * <tt>change_column_null(table_name, column_name, null, default = nil)</tt>: + # Sets or removes a +NOT NULL+ constraint on +column_name+. The +null+ flag + # indicates whether the value can be +NULL+. See + # ActiveRecord::ConnectionAdapters::SchemaStatements#change_column_null for + # details. + # * <tt>change_table(name, options)</tt>: Allows to make column alterations to + # the table called +name+. It makes the table object available to a block that + # can then add/remove columns, indexes or foreign keys to it. + # * <tt>rename_column(table_name, column_name, new_column_name)</tt>: Renames + # a column but keeps the type and content. + # * <tt>rename_index(table_name, old_name, new_name)</tt>: Renames an index. + # * <tt>rename_table(old_name, new_name)</tt>: Renames the table called +old_name+ + # to +new_name+. + # + # === Deletion + # + # * <tt>drop_table(name)</tt>: Drops the table called +name+. + # * <tt>drop_join_table(table_1, table_2, options)</tt>: Drops the join table + # specified by the given arguments. + # * <tt>remove_column(table_name, column_name, type, options)</tt>: Removes the column + # named +column_name+ from the table called +table_name+. + # * <tt>remove_columns(table_name, *column_names)</tt>: Removes the given + # columns from the table definition. + # * <tt>remove_foreign_key(from_table, options_or_to_table)</tt>: Removes the + # given foreign key from the table called +table_name+. # * <tt>remove_index(table_name, column: column_names)</tt>: Removes the index # specified by +column_names+. # * <tt>remove_index(table_name, name: index_name)</tt>: Removes the index # specified by +index_name+. - # * <tt>add_reference(:table_name, :reference_name)</tt>: Adds a new column - # +reference_name_id+ by default an integer. See - # ActiveRecord::ConnectionAdapters::SchemaStatements#add_reference for details. + # * <tt>remove_reference(table_name, ref_name, options)</tt>: Removes the + # reference(s) on +table_name+ specified by +ref_name+. + # * <tt>remove_timestamps(table_name, options)</tt>: Removes the timestamp + # columns (+created_at+ and +updated_at+) from the table definition. # # == Irreversible transformations # |