diff options
Diffstat (limited to 'activerecord/lib/active_record')
| -rw-r--r-- | activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb | 312 |
1 files changed, 190 insertions, 122 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb index 7b8606ccc9..0f35f852f5 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb @@ -5,7 +5,7 @@ module ActiveRecord module SchemaStatements include ActiveRecord::Migration::JoinTable - # Returns a Hash of mappings from the abstract data types to the native + # Returns a hash of mappings from the abstract data types to the native # database types. See TableDefinition#column for details on the recognized # abstract data types. def native_database_types @@ -20,6 +20,7 @@ module ActiveRecord # Checks to see if the table +table_name+ exists on the database. # # table_exists?(:developers) + # def table_exists?(table_name) tables.include?(table_name.to_s) end @@ -29,17 +30,18 @@ module ActiveRecord # Checks to see if an index exists on a table for a given index definition. # - # # Check an index exists - # index_exists?(:suppliers, :company_id) + # # Check an index exists + # index_exists?(:suppliers, :company_id) + # + # # Check an index on multiple columns exists + # index_exists?(:suppliers, [:company_id, :company_type]) # - # # Check an index on multiple columns exists - # index_exists?(:suppliers, [:company_id, :company_type]) + # # Check a unique index exists + # index_exists?(:suppliers, :company_id, unique: true) # - # # Check a unique index exists - # index_exists?(:suppliers, :company_id, unique: true) + # # Check an index with a custom name exists + # index_exists?(:suppliers, :company_id, name: "idx_company_id" # - # # Check an index with a custom name exists - # index_exists?(:suppliers, :company_id, name: "idx_company_id" def index_exists?(table_name, column_name, options = {}) column_names = Array(column_name) index_name = options.key?(:name) ? options[:name].to_s : index_name(table_name, :column => column_names) @@ -56,17 +58,18 @@ module ActiveRecord # Checks to see if a column exists in a given table. # - # # Check a column exists - # column_exists?(:suppliers, :name) + # # Check a column exists + # column_exists?(:suppliers, :name) + # + # # Check a column exists of a particular type + # column_exists?(:suppliers, :name, :string) # - # # Check a column exists of a particular type - # column_exists?(:suppliers, :name, :string) + # # Check a column exists with a specific definition + # column_exists?(:suppliers, :name, :string, limit: 100) + # column_exists?(:suppliers, :name, :string, default: 'default') + # column_exists?(:suppliers, :name, :string, null: false) + # column_exists?(:suppliers, :tax, :decimal, precision: 8, scale: 2) # - # # Check a column exists with a specific definition - # column_exists?(:suppliers, :name, :string, limit: 100) - # column_exists?(:suppliers, :name, :string, default: 'default') - # column_exists?(:suppliers, :name, :string, null: false) - # column_exists?(:suppliers, :tax, :decimal, precision: 8, scale: 2) def column_exists?(table_name, column_name, type = nil, options = {}) columns(table_name).any?{ |c| c.name == column_name.to_s && (!type || c.type == type) && @@ -84,27 +87,30 @@ module ActiveRecord # form or the regular form, like this: # # === Block form - # # create_table() passes a TableDefinition object to the block. - # # This form will not only create the table, but also columns for the - # # table. # - # create_table(:suppliers) do |t| - # t.column :name, :string, limit: 60 - # # Other fields here - # end + # # create_table() passes a TableDefinition object to the block. + # # This form will not only create the table, but also columns for the + # # table. + # + # create_table(:suppliers) do |t| + # t.column :name, :string, limit: 60 + # # Other fields here + # end # # === Block form, with shorthand - # # You can also use the column types as method calls, rather than calling the column method. - # create_table(:suppliers) do |t| - # t.string :name, limit: 60 - # # Other fields here - # end + # + # # You can also use the column types as method calls, rather than calling the column method. + # create_table(:suppliers) do |t| + # t.string :name, limit: 60 + # # Other fields here + # end # # === Regular form - # # Creates a table called 'suppliers' with no columns. - # create_table(:suppliers) - # # Add a column to 'suppliers'. - # add_column(:suppliers, :name, :string, {limit: 60}) + # + # # Creates a table called 'suppliers' with no columns. + # create_table(:suppliers) + # # Add a column to 'suppliers'. + # add_column(:suppliers, :name, :string, {limit: 60}) # # The +options+ hash can include the following keys: # [<tt>:id</tt>] @@ -127,32 +133,41 @@ module ActiveRecord # Defaults to false. # # ====== Add a backend specific option to the generated SQL (MySQL) - # create_table(:suppliers, options: 'ENGINE=InnoDB DEFAULT CHARSET=utf8') + # + # create_table(:suppliers, options: 'ENGINE=InnoDB DEFAULT CHARSET=utf8') + # # generates: - # CREATE TABLE suppliers ( - # id int(11) DEFAULT NULL auto_increment PRIMARY KEY - # ) ENGINE=InnoDB DEFAULT CHARSET=utf8 + # + # CREATE TABLE suppliers ( + # id int(11) DEFAULT NULL auto_increment PRIMARY KEY + # ) ENGINE=InnoDB DEFAULT CHARSET=utf8 # # ====== Rename the primary key column - # create_table(:objects, primary_key: 'guid') do |t| - # t.column :name, :string, limit: 80 - # end + # + # create_table(:objects, primary_key: 'guid') do |t| + # t.column :name, :string, limit: 80 + # end + # # generates: - # CREATE TABLE objects ( - # guid int(11) DEFAULT NULL auto_increment PRIMARY KEY, - # name varchar(80) - # ) + # + # CREATE TABLE objects ( + # guid int(11) DEFAULT NULL auto_increment PRIMARY KEY, + # name varchar(80) + # ) # # ====== Do not add a primary key column - # create_table(:categories_suppliers, id: false) do |t| - # t.column :category_id, :integer - # t.column :supplier_id, :integer - # end + # + # create_table(:categories_suppliers, id: false) do |t| + # t.column :category_id, :integer + # t.column :supplier_id, :integer + # end + # # generates: - # CREATE TABLE categories_suppliers ( - # category_id int, - # supplier_id int - # ) + # + # CREATE TABLE categories_suppliers ( + # category_id int, + # supplier_id int + # ) # # See also TableDefinition#column for details on how to create columns. def create_table(table_name, options = {}) @@ -176,8 +191,8 @@ module ActiveRecord # Creates a new join table with the name created using the lexical order of the first two # arguments. These arguments can be a String or a Symbol. # - # # Creates a table called 'assemblies_parts' with no id. - # create_join_table(:assemblies, :parts) + # # Creates a table called 'assemblies_parts' with no id. + # create_join_table(:assemblies, :parts) # # You can pass a +options+ hash can include the following keys: # [<tt>:table_name</tt>] @@ -201,12 +216,16 @@ module ActiveRecord # end # # ====== Add a backend specific option to the generated SQL (MySQL) - # create_join_table(:assemblies, :parts, options: 'ENGINE=InnoDB DEFAULT CHARSET=utf8') + # + # create_join_table(:assemblies, :parts, options: 'ENGINE=InnoDB DEFAULT CHARSET=utf8') + # # generates: - # CREATE TABLE assemblies_parts ( - # assembly_id int NOT NULL, - # part_id int NOT NULL, - # ) ENGINE=InnoDB DEFAULT CHARSET=utf8 + # + # CREATE TABLE assemblies_parts ( + # assembly_id int NOT NULL, + # part_id int NOT NULL, + # ) ENGINE=InnoDB DEFAULT CHARSET=utf8 + # def create_join_table(table_1, table_2, options = {}) join_table_name = find_join_table_name(table_1, table_2, options) @@ -223,7 +242,7 @@ module ActiveRecord end # Drops the join table specified by the given arguments. - # See create_join_table for details. + # See +create_join_table+ for details. # # Although this command ignores the block if one is given, it can be helpful # to provide one in a migration's +change+ method so it can be reverted. @@ -235,66 +254,74 @@ module ActiveRecord # A block for changing columns in +table+. # - # # change_table() yields a Table instance - # change_table(:suppliers) do |t| - # t.column :name, :string, limit: 60 - # # Other column alterations here - # end + # # change_table() yields a Table instance + # change_table(:suppliers) do |t| + # t.column :name, :string, limit: 60 + # # Other column alterations here + # end # # The +options+ hash can include the following keys: # [<tt>:bulk</tt>] # Set this to true to make this a bulk alter query, such as - # ALTER TABLE `users` ADD COLUMN age INT(11), ADD COLUMN birthdate DATETIME ... + # + # ALTER TABLE `users` ADD COLUMN age INT(11), ADD COLUMN birthdate DATETIME ... # # Defaults to false. # # ====== Add a column - # change_table(:suppliers) do |t| - # t.column :name, :string, limit: 60 - # end + # + # change_table(:suppliers) do |t| + # t.column :name, :string, limit: 60 + # end # # ====== Add 2 integer columns - # change_table(:suppliers) do |t| - # t.integer :width, :height, null: false, default: 0 - # end + # + # change_table(:suppliers) do |t| + # t.integer :width, :height, null: false, default: 0 + # end # # ====== Add created_at/updated_at columns - # change_table(:suppliers) do |t| - # t.timestamps - # end + # + # change_table(:suppliers) do |t| + # t.timestamps + # end # # ====== Add a foreign key column - # change_table(:suppliers) do |t| - # t.references :company - # end # - # Creates a <tt>company_id(integer)</tt> column + # change_table(:suppliers) do |t| + # t.references :company + # end + # + # Creates a <tt>company_id(integer)</tt> column. # # ====== Add a polymorphic foreign key column + # # change_table(:suppliers) do |t| # t.belongs_to :company, polymorphic: true # end # - # Creates <tt>company_type(varchar)</tt> and <tt>company_id(integer)</tt> columns + # Creates <tt>company_type(varchar)</tt> and <tt>company_id(integer)</tt> columns. # # ====== Remove a column + # # change_table(:suppliers) do |t| # t.remove :company # end # # ====== Remove several columns + # # change_table(:suppliers) do |t| # t.remove :company_id # t.remove :width, :height # end # # ====== Remove an index + # # change_table(:suppliers) do |t| # t.remove_index :company_id # end # - # See also Table for details on - # all of the various column transformation + # See also Table for details on all of the various column transformation. def change_table(table_name, options = {}) if supports_bulk_alter? && options[:bulk] recorder = ActiveRecord::Migration::CommandRecorder.new(self) @@ -307,7 +334,8 @@ module ActiveRecord # Renames a table. # - # rename_table('octopuses', 'octopi') + # rename_table('octopuses', 'octopi') + # def rename_table(table_name, new_name) raise NotImplementedError, "rename_table is not implemented" end @@ -331,7 +359,8 @@ module ActiveRecord # Removes the given columns from the table definition. # - # remove_columns(:suppliers, :qualification, :experience) + # remove_columns(:suppliers, :qualification, :experience) + # def remove_columns(table_name, *column_names) raise ArgumentError.new("You must specify at least one column name. Example: remove_columns(:people, :first_name)") if column_names.empty? column_names.each do |column_name| @@ -341,7 +370,7 @@ module ActiveRecord # Removes the column from the table definition. # - # remove_column(:suppliers, :qualification) + # remove_column(:suppliers, :qualification) # # The +type+ and +options+ parameters will be ignored if present. It can be helpful # to provide these in a migration's +change+ method so it can be reverted. @@ -353,8 +382,9 @@ module ActiveRecord # Changes the column's definition according to the new options. # See TableDefinition#column for details of the options you can use. # - # change_column(:suppliers, :name, :string, limit: 80) - # change_column(:accounts, :description, :text) + # change_column(:suppliers, :name, :string, limit: 80) + # change_column(:accounts, :description, :text) + # def change_column(table_name, column_name, type, options = {}) raise NotImplementedError, "change_column is not implemented" end @@ -366,7 +396,7 @@ module ActiveRecord # # Setting the default to +nil+ effectively drops the default: # - # change_column_default(:users, :email, nil) + # change_column_default(:users, :email, nil) # def change_column_default(table_name, column_name, default) raise NotImplementedError, "change_column_default is not implemented" @@ -374,7 +404,8 @@ module ActiveRecord # Renames a column. # - # rename_column(:suppliers, :description, :name) + # rename_column(:suppliers, :description, :name) + # def rename_column(table_name, column_name, new_column_name) raise NotImplementedError, "rename_column is not implemented" end @@ -386,60 +417,87 @@ module ActiveRecord # you pass <tt>:name</tt> as an option. # # ====== Creating a simple index - # add_index(:suppliers, :name) + # + # add_index(:suppliers, :name) + # # generates - # CREATE INDEX suppliers_name_index ON suppliers(name) + # + # CREATE INDEX suppliers_name_index ON suppliers(name) # # ====== Creating a unique index - # add_index(:accounts, [:branch_id, :party_id], unique: true) + # + # add_index(:accounts, [:branch_id, :party_id], unique: true) + # # generates - # CREATE UNIQUE INDEX accounts_branch_id_party_id_index ON accounts(branch_id, party_id) + # + # CREATE UNIQUE INDEX accounts_branch_id_party_id_index ON accounts(branch_id, party_id) # # ====== Creating a named index - # add_index(:accounts, [:branch_id, :party_id], unique: true, name: 'by_branch_party') + # + # add_index(:accounts, [:branch_id, :party_id], unique: true, name: 'by_branch_party') + # # generates + # # CREATE UNIQUE INDEX by_branch_party ON accounts(branch_id, party_id) # # ====== Creating an index with specific key length - # add_index(:accounts, :name, name: 'by_name', length: 10) + # + # add_index(:accounts, :name, name: 'by_name', length: 10) + # # generates - # CREATE INDEX by_name ON accounts(name(10)) # - # add_index(:accounts, [:name, :surname], name: 'by_name_surname', length: {name: 10, surname: 15}) + # CREATE INDEX by_name ON accounts(name(10)) + # + # add_index(:accounts, [:name, :surname], name: 'by_name_surname', length: {name: 10, surname: 15}) + # # generates - # CREATE INDEX by_name_surname ON accounts(name(10), surname(15)) # - # Note: SQLite doesn't support index length + # CREATE INDEX by_name_surname ON accounts(name(10), surname(15)) + # + # Note: SQLite doesn't support index length. # # ====== Creating an index with a sort order (desc or asc, asc is the default) - # add_index(:accounts, [:branch_id, :party_id, :surname], order: {branch_id: :desc, party_id: :asc}) + # + # add_index(:accounts, [:branch_id, :party_id, :surname], order: {branch_id: :desc, party_id: :asc}) + # # generates - # CREATE INDEX by_branch_desc_party ON accounts(branch_id DESC, party_id ASC, surname) # - # Note: mysql doesn't yet support index order (it accepts the syntax but ignores it) + # CREATE INDEX by_branch_desc_party ON accounts(branch_id DESC, party_id ASC, surname) + # + # Note: MySQL doesn't yet support index order (it accepts the syntax but ignores it). # # ====== Creating a partial index - # add_index(:accounts, [:branch_id, :party_id], unique: true, where: "active") + # + # add_index(:accounts, [:branch_id, :party_id], unique: true, where: "active") + # # generates - # CREATE UNIQUE INDEX index_accounts_on_branch_id_and_party_id ON accounts(branch_id, party_id) WHERE active # - # Note: only supported by PostgreSQL + # CREATE UNIQUE INDEX index_accounts_on_branch_id_and_party_id ON accounts(branch_id, party_id) WHERE active # + # Note: only supported by PostgreSQL. def add_index(table_name, column_name, options = {}) index_name, index_type, index_columns, index_options = add_index_options(table_name, column_name, options) execute "CREATE #{index_type} INDEX #{quote_column_name(index_name)} ON #{quote_table_name(table_name)} (#{index_columns})#{index_options}" end - # Remove the given index from the table. + # Removes the given index from the table. + # + # Removes the +index_accounts_on_column+ in the +accounts+ table. # - # Remove the index_accounts_on_column in the accounts table. # remove_index :accounts, :column - # Remove the index named index_accounts_on_branch_id in the accounts table. + # + # Removes the index named +index_accounts_on_branch_id+ in the +accounts+ table. + # # remove_index :accounts, column: :branch_id - # Remove the index named index_accounts_on_branch_id_and_party_id in the accounts table. + # + # Removes the index named +index_accounts_on_branch_id_and_party_id+ in the +accounts+ table. + # # remove_index :accounts, column: [:branch_id, :party_id] - # Remove the index named by_branch_party in the accounts table. + # + # Removes the index named +by_branch_party+ in the +accounts+ table. + # # remove_index :accounts, name: :by_branch_party + # def remove_index(table_name, options = {}) remove_index!(table_name, index_name_for_remove(table_name, options)) end @@ -448,10 +506,12 @@ module ActiveRecord execute "DROP INDEX #{quote_column_name(index_name)} ON #{quote_table_name(table_name)}" end - # Rename an index. + # Renames an index. + # + # Rename the +index_people_on_last_name+ index to +index_users_on_last_name+: # - # Rename the index_people_on_last_name index to index_users_on_last_name # rename_index :people, 'index_people_on_last_name', 'index_users_on_last_name' + # def rename_index(table_name, old_name, new_name) # this is a naive implementation; some DBs may support this more efficiently (Postgres, for instance) old_index_def = indexes(table_name).detect { |i| i.name == old_name } @@ -474,7 +534,7 @@ module ActiveRecord end end - # Verify the existence of an index with a given name. + # Verifies the existence of an index with a given name. # # The default argument is returned if the underlying implementation does not define the indexes method, # as there's no way to determine the correct answer in that case. @@ -488,13 +548,16 @@ module ActiveRecord # <tt>add_reference</tt> and <tt>add_belongs_to</tt> are acceptable. # # ====== Create a user_id column - # add_reference(:products, :user) + # + # add_reference(:products, :user) # # ====== Create a supplier_id and supplier_type columns - # add_belongs_to(:products, :supplier, polymorphic: true) + # + # add_belongs_to(:products, :supplier, polymorphic: true) # # ====== Create a supplier_id, supplier_type columns and appropriate index - # add_reference(:products, :supplier, polymorphic: true, index: true) + # + # add_reference(:products, :supplier, polymorphic: true, index: true) # def add_reference(table_name, ref_name, options = {}) polymorphic = options.delete(:polymorphic) @@ -509,10 +572,12 @@ module ActiveRecord # <tt>remove_reference</tt>, <tt>remove_references</tt> and <tt>remove_belongs_to</tt> are acceptable. # # ====== Remove the reference - # remove_reference(:products, :user, index: true) + # + # remove_reference(:products, :user, index: true) # # ====== Remove polymorphic reference - # remove_reference(:products, :supplier, polymorphic: true) + # + # remove_reference(:products, :supplier, polymorphic: true) # def remove_reference(table_name, ref_name, options = {}) remove_column(table_name, "#{ref_name}_id") @@ -599,21 +664,24 @@ module ActiveRecord # Both PostgreSQL and Oracle overrides this for custom DISTINCT syntax. # # distinct("posts.id", "posts.created_at desc") + # def distinct(columns, order_by) "DISTINCT #{columns}" end - # Adds timestamps (created_at and updated_at) columns to the named table. + # Adds timestamps (+created_at+ and +updated_at+) columns to the named table. + # + # add_timestamps(:suppliers) # - # add_timestamps(:suppliers) def add_timestamps(table_name) add_column table_name, :created_at, :datetime add_column table_name, :updated_at, :datetime end - # Removes the timestamp columns (created_at and updated_at) from the table definition. + # Removes the timestamp columns (+created_at+ and +updated_at+) from the table definition. # # remove_timestamps(:suppliers) + # def remove_timestamps(table_name) remove_column table_name, :updated_at remove_column table_name, :created_at |