# frozen_string_literal: true require "active_support/core_ext/string/access" require "openssl" module ActiveRecord module ConnectionAdapters # :nodoc: module SchemaStatements include ActiveRecord::Migration::JoinTable # 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 {} end def table_options(table_name) nil end # Returns the table comment that's stored in database metadata. def table_comment(table_name) nil end # Truncates a table alias according to the limits of the current adapter. def table_alias_for(table_name) table_name[0...table_alias_length].tr(".", "_") end # Returns the relation names usable to back Active Record models. # For most adapters this means all #tables and #views. def data_sources query_values(data_source_sql, "SCHEMA") rescue NotImplementedError tables | views end # Checks to see if the data source +name+ exists on the database. # # data_source_exists?(:ebooks) # def data_source_exists?(name) query_values(data_source_sql(name), "SCHEMA").any? if name.present? rescue NotImplementedError data_sources.include?(name.to_s) end # Returns an array of table names defined in the database. def tables query_values(data_source_sql(type: "BASE TABLE"), "SCHEMA") end # Checks to see if the table +table_name+ exists on the database. # # table_exists?(:developers) # def table_exists?(table_name) query_values(data_source_sql(table_name, type: "BASE TABLE"), "SCHEMA").any? if table_name.present? rescue NotImplementedError tables.include?(table_name.to_s) end # Returns an array of view names defined in the database. def views query_values(data_source_sql(type: "VIEW"), "SCHEMA") end # Checks to see if the view +view_name+ exists on the database. # # view_exists?(:ebooks) # def view_exists?(view_name) query_values(data_source_sql(view_name, type: "VIEW"), "SCHEMA").any? if view_name.present? rescue NotImplementedError views.include?(view_name.to_s) end # Returns an array of indexes for the given table. def indexes(table_name) raise NotImplementedError, "#indexes is not implemented" end # 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 on multiple columns exists # index_exists?(:suppliers, [:company_id, :company_type]) # # # 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 a valid index exists (PostgreSQL only) # index_exists?(:suppliers, :company_id, valid: true) # def index_exists?(table_name, column_name, **options) indexes(table_name).any? { |i| i.defined_for?(column_name, **options) } end # Returns an array of +Column+ objects for the table specified by +table_name+. def columns(table_name) table_name = table_name.to_s definitions = column_definitions(table_name) definitions.map do |field| new_column_from_field(table_name, field, definitions) end end # Checks to see if a column exists in a given table. # # # Check a column exists # column_exists?(:suppliers, :name) # # # Check a column exists of a particular type # # # # This works for standard non-casted types (eg. string) but is unreliable # # for types that may get cast to something else (eg. char, bigint). # 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) # def column_exists?(table_name, column_name, type = nil, **options) column_name = column_name.to_s checks = [] checks << lambda { |c| c.name == column_name } checks << lambda { |c| c.type == type.to_sym rescue nil } if type column_options_keys.each do |attr| checks << lambda { |c| c.send(attr) == options[attr] } if options.key?(attr) end columns(table_name).any? { |c| checks.all? { |check| check[c] } } end # Returns just a table's primary key def primary_key(table_name) pk = primary_keys(table_name) pk = pk.first unless pk.size > 1 pk end # Creates a new table with the name +table_name+. +table_name+ may either # be a String or a Symbol. # # There are two ways to work with #create_table. You can use the block # 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 # # === 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 # # === 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}) # # The +options+ hash can include the following keys: # [:id] # Whether to automatically add a primary key column. Defaults to true. # Join tables for {ActiveRecord::Base.has_and_belongs_to_many}[rdoc-ref:Associations::ClassMethods#has_and_belongs_to_many] should set it to false. # # A Symbol can be used to specify the type of the generated primary key column. # [:primary_key] # The name of the primary key, if one is to be added automatically. # Defaults to +id+. If :id is false, then this option is ignored. # # If an array is passed, a composite primary key will be created. # # Note that Active Record models will automatically detect their # primary key. This can be avoided by using # {self.primary_key=}[rdoc-ref:AttributeMethods::PrimaryKey::ClassMethods#primary_key=] on the model # to define the key explicitly. # # [:options] # Any extra options you want appended to the table definition. # [:temporary] # Make a temporary table. # [:force] # Set to true to drop the table before creating it. # Set to +:cascade+ to drop dependent objects as well. # Defaults to false. # [:if_not_exists] # Set to true to avoid raising an error when the table already exists. # Defaults to false. # [:as] # SQL to use to generate the table. When this option is used, the block is # ignored, as are the :id and :primary_key options. # # ====== Add a backend specific option to the generated SQL (MySQL) # # create_table(:suppliers, options: 'ENGINE=InnoDB DEFAULT CHARSET=utf8mb4') # # generates: # # CREATE TABLE suppliers ( # id bigint auto_increment PRIMARY KEY # ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 # # ====== Rename the primary key column # # create_table(:objects, primary_key: 'guid') do |t| # t.column :name, :string, limit: 80 # end # # generates: # # CREATE TABLE objects ( # guid bigint auto_increment PRIMARY KEY, # name varchar(80) # ) # # ====== Change the primary key column type # # create_table(:tags, id: :string) do |t| # t.column :label, :string # end # # generates: # # CREATE TABLE tags ( # id varchar PRIMARY KEY, # label varchar # ) # # ====== Create a composite primary key # # create_table(:orders, primary_key: [:product_id, :client_id]) do |t| # t.belongs_to :product # t.belongs_to :client # end # # generates: # # CREATE TABLE orders ( # product_id bigint NOT NULL, # client_id bigint NOT NULL # ); # # ALTER TABLE ONLY "orders" # ADD CONSTRAINT orders_pkey PRIMARY KEY (product_id, client_id); # # ====== Do not add a primary key column # # create_table(:categories_suppliers, id: false) do |t| # t.column :category_id, :bigint # t.column :supplier_id, :bigint # end # # generates: # # CREATE TABLE categories_suppliers ( # category_id bigint, # supplier_id bigint # ) # # ====== Create a temporary table based on a query # # create_table(:long_query, temporary: true, # as: "SELECT * FROM orders INNER JOIN line_items ON order_id=orders.id") # # generates: # # CREATE TEMPORARY TABLE long_query AS # SELECT * FROM orders INNER JOIN line_items ON order_id=orders.id # # See also TableDefinition#column for details on how to create columns. def create_table(table_name, id: :primary_key, primary_key: nil, force: nil, **options, &block) validate_create_table_options!(options) validate_table_length!(table_name) unless options[:_uses_legacy_table_name] td = build_create_table_definition(table_name, id: id, primary_key: primary_key, force: force, **options, &block) if force drop_table(table_name, force: force, if_exists: true) else schema_cache.clear_data_source_cache!(table_name.to_s) end result = execute schema_creation.accept(td) unless supports_indexes_in_create? td.indexes.each do |column_name, index_options| add_index(table_name, column_name, **index_options, if_not_exists: td.if_not_exists) end end if supports_comments? && !supports_comments_in_create? if table_comment = td.comment.presence change_table_comment(table_name, table_comment) end td.columns.each do |column| change_column_comment(table_name, column.name, column.comment) if column.comment.present? end end result end # Returns a TableDefinition object containing information about the table that would be created # if the same arguments were passed to #create_table. See #create_table for information about # passing a +table_name+, and other additional options that can be passed. def build_create_table_definition(table_name, id: :primary_key, primary_key: nil, force: nil, **options) table_definition = create_table_definition(table_name, **options.extract!(*valid_table_definition_options, :_skip_validate_options)) table_definition.set_primary_key(table_name, id, primary_key, **options.extract!(*valid_primary_key_options, :_skip_validate_options)) yield table_definition if block_given? table_definition end # 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) # # You can pass an +options+ hash which can include the following keys: # [:table_name] # Sets the table name, overriding the default. # [:column_options] # Any extra options you want appended to the columns definition. # [:options] # Any extra options you want appended to the table definition. # [:temporary] # Make a temporary table. # [:force] # Set to true to drop the table before creating it. # Defaults to false. # # Note that #create_join_table does not create any indices by default; you can use # its block form to do so yourself: # # create_join_table :products, :categories do |t| # t.index :product_id # t.index :category_id # end # # ====== Add a backend specific option to the generated SQL (MySQL) # # create_join_table(:assemblies, :parts, options: 'ENGINE=InnoDB DEFAULT CHARSET=utf8') # # generates: # # CREATE TABLE assemblies_parts ( # assembly_id bigint NOT NULL, # part_id bigint NOT NULL, # ) ENGINE=InnoDB DEFAULT CHARSET=utf8 # def create_join_table(table_1, table_2, column_options: {}, **options) join_table_name = find_join_table_name(table_1, table_2, options) column_options.reverse_merge!(null: false, index: false) t1_ref, t2_ref = [table_1, table_2].map { |t| reference_name_for_table(t) } create_table(join_table_name, **options.merge!(id: false)) do |td| td.references t1_ref, **column_options td.references t2_ref, **column_options yield td if block_given? end end # Builds a TableDefinition object for a join table. # # This definition object contains information about the table that would be created # if the same arguments were passed to #create_join_table. See #create_join_table for # information about what arguments should be passed. def build_create_join_table_definition(table_1, table_2, column_options: {}, **options) # :nodoc: join_table_name = find_join_table_name(table_1, table_2, options) column_options.reverse_merge!(null: false, index: false) t1_ref, t2_ref = [table_1, table_2].map { |t| reference_name_for_table(t) } build_create_table_definition(join_table_name, **options.merge!(id: false)) do |td| td.references t1_ref, **column_options td.references t2_ref, **column_options yield td if block_given? end end # Drops the join table specified by the given arguments. # See #create_join_table and #drop_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. # In that case, the block will be used by #create_join_table. def drop_join_table(table_1, table_2, **options) join_table_name = find_join_table_name(table_1, table_2, options) drop_table(join_table_name, **options) end # 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 # # The +options+ hash can include the following keys: # [:bulk] # Set this to true to make this a bulk alter query, such as # # ALTER TABLE `users` ADD COLUMN age INT, ADD COLUMN birthdate DATETIME ... # # Defaults to false. # # Only supported on the MySQL and PostgreSQL adapter, ignored elsewhere. # # ====== Add a column # # change_table(:suppliers) do |t| # t.column :name, :string, limit: 60 # end # # ====== Change type of a column # # change_table(:suppliers) do |t| # t.change :metadata, :json # end # # ====== Add 2 integer columns # # 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 # # ====== Add a foreign key column # # change_table(:suppliers) do |t| # t.references :company # end # # Creates a company_id(bigint) column. # # ====== Add a polymorphic foreign key column # # change_table(:suppliers) do |t| # t.belongs_to :company, polymorphic: true # end # # Creates company_type(varchar) and company_id(bigint) 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 transformations. def change_table(table_name, base = self, **options) if supports_bulk_alter? && options[:bulk] recorder = ActiveRecord::Migration::CommandRecorder.new(self) yield update_table_definition(table_name, recorder) bulk_change_table(table_name, recorder.commands) else yield update_table_definition(table_name, base) end end # Renames a table. # # rename_table('octopuses', 'octopi') # def rename_table(table_name, new_name, **) raise NotImplementedError, "rename_table is not implemented" end # Drops a table from the database. # # [:force] # Set to +:cascade+ to drop dependent objects as well. # Defaults to false. # [:if_exists] # Set to +true+ to only drop the table if it exists. # Defaults to false. # # Although this command ignores most +options+ and the block if one is given, # it can be helpful to provide these in a migration's +change+ method so it can be reverted. # In that case, +options+ and the block will be used by #create_table. def drop_table(table_name, **options) schema_cache.clear_data_source_cache!(table_name.to_s) execute "DROP TABLE#{' IF EXISTS' if options[:if_exists]} #{quote_table_name(table_name)}" end # Add a new +type+ column named +column_name+ to +table_name+. # # See {ActiveRecord::ConnectionAdapters::TableDefinition.column}[rdoc-ref:ActiveRecord::ConnectionAdapters::TableDefinition#column]. # # The +type+ parameter is normally one of the migrations native types, # which is one of the following: # :primary_key, :string, :text, # :integer, :bigint, :float, :decimal, :numeric, # :datetime, :time, :date, # :binary, :blob, :boolean. # # You may use a type not in this list as long as it is supported by your # database (for example, "polygon" in MySQL), but this will not be database # agnostic and should usually be avoided. # # Available options are (none of these exists by default): # * :comment - # Specifies the comment for the column. This option is ignored by some backends. # * :collation - # Specifies the collation for a :string or :text column. # If not specified, the column will have the same collation as the table. # * :default - # The column's default value. Use +nil+ for +NULL+. # * :limit - # Requests a maximum column length. This is the number of characters for a :string column # and number of bytes for :text, :binary, :blob, and :integer columns. # This option is ignored by some backends. # * :null - # Allows or disallows +NULL+ values in the column. # * :precision - # Specifies the precision for the :decimal, :numeric, # :datetime, and :time columns. # * :scale - # Specifies the scale for the :decimal and :numeric columns. # * :if_not_exists - # Specifies if the column already exists to not try to re-add it. This will avoid # duplicate column errors. # # Note: The precision is the total number of significant digits, # and the scale is the number of digits that can be stored following # the decimal point. For example, the number 123.45 has a precision of 5 # and a scale of 2. A decimal with a precision of 5 and a scale of 2 can # range from -999.99 to 999.99. # # Please be aware of different RDBMS implementations behavior with # :decimal columns: # * The SQL standard says the default scale should be 0, :scale <= # :precision, and makes no comments about the requirements of # :precision. # * MySQL: :precision [1..65], :scale [0..30]. # Default is (10,0). # * PostgreSQL: :precision [1..infinity], # :scale [0..infinity]. No default. # * SQLite3: No restrictions on :precision and :scale, # but the maximum supported :precision is 16. No default. # * Oracle: :precision [1..38], :scale [-84..127]. # Default is (38,0). # * SqlServer: :precision [1..38], :scale [0..38]. # Default (38,0). # # == Examples # # add_column(:users, :picture, :binary, limit: 2.megabytes) # # ALTER TABLE "users" ADD "picture" blob(2097152) # # add_column(:articles, :status, :string, limit: 20, default: 'draft', null: false) # # ALTER TABLE "articles" ADD "status" varchar(20) DEFAULT 'draft' NOT NULL # # add_column(:answers, :bill_gates_money, :decimal, precision: 15, scale: 2) # # ALTER TABLE "answers" ADD "bill_gates_money" decimal(15,2) # # add_column(:measurements, :sensor_reading, :decimal, precision: 30, scale: 20) # # ALTER TABLE "measurements" ADD "sensor_reading" decimal(30,20) # # # While :scale defaults to zero on most databases, it # # probably wouldn't hurt to include it. # add_column(:measurements, :huge_integer, :decimal, precision: 30) # # ALTER TABLE "measurements" ADD "huge_integer" decimal(30) # # # Defines a column that stores an array of a type. # add_column(:users, :skills, :text, array: true) # # ALTER TABLE "users" ADD "skills" text[] # # # Defines a column with a database-specific type. # add_column(:shapes, :triangle, 'polygon') # # ALTER TABLE "shapes" ADD "triangle" polygon # # # Ignores the method call if the column exists # add_column(:shapes, :triangle, 'polygon', if_not_exists: true) def add_column(table_name, column_name, type, **options) add_column_def = build_add_column_definition(table_name, column_name, type, **options) return unless add_column_def execute schema_creation.accept(add_column_def) end def add_columns(table_name, *column_names, type:, **options) # :nodoc: column_names.each do |column_name| add_column(table_name, column_name, type, **options) end end # Builds an AlterTable object for adding a column to a table. # # This definition object contains information about the column that would be created # if the same arguments were passed to #add_column. See #add_column for information about # passing a +table_name+, +column_name+, +type+ and other options that can be passed. def build_add_column_definition(table_name, column_name, type, **options) # :nodoc: return if options[:if_not_exists] == true && column_exists?(table_name, column_name) if supports_datetime_with_precision? if type == :datetime && !options.key?(:precision) options[:precision] = 6 end end alter_table = create_alter_table(table_name) alter_table.add_column(column_name, type, **options) alter_table end # Removes the given columns from the table definition. # # remove_columns(:suppliers, :qualification, :experience) # # +type+ and other column options can be passed to make migration reversible. # # remove_columns(:suppliers, :qualification, :experience, type: :string, null: false) def remove_columns(table_name, *column_names, type: nil, **options) if column_names.empty? raise ArgumentError.new("You must specify at least one column name. Example: remove_columns(:people, :first_name)") end remove_column_fragments = remove_columns_for_alter(table_name, *column_names, type: type, **options) execute "ALTER TABLE #{quote_table_name(table_name)} #{remove_column_fragments.join(', ')}" end # Removes the column from the table definition. # # 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. # In that case, +type+ and +options+ will be used by #add_column. # Depending on the database you're using, indexes using this column may be # automatically removed or modified to remove this column from the index. # # If the options provided include an +if_exists+ key, it will be used to check if the # column does not exist. This will silently ignore the migration rather than raising # if the column was already used. # # remove_column(:suppliers, :qualification, if_exists: true) def remove_column(table_name, column_name, type = nil, **options) return if options[:if_exists] == true && !column_exists?(table_name, column_name) execute "ALTER TABLE #{quote_table_name(table_name)} #{remove_column_for_alter(table_name, column_name, type, **options)}" end # 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) # def change_column(table_name, column_name, type, **options) raise NotImplementedError, "change_column is not implemented" end # Sets a new default value for a column: # # change_column_default(:suppliers, :qualification, 'new') # change_column_default(:accounts, :authorized, 1) # # Setting the default to +nil+ effectively drops the default: # # change_column_default(:users, :email, nil) # # Passing a hash containing +:from+ and +:to+ will make this change # reversible in migration: # # change_column_default(:posts, :state, from: nil, to: "draft") # def change_column_default(table_name, column_name, default_or_changes) raise NotImplementedError, "change_column_default is not implemented" end # Builds a ChangeColumnDefaultDefinition object. # # This definition object contains information about the column change that would occur # if the same arguments were passed to #change_column_default. See #change_column_default for # information about passing a +table_name+, +column_name+, +type+ and other options that can be passed. def build_change_column_default_definition(table_name, column_name, default_or_changes) # :nodoc: raise NotImplementedError, "build_change_column_default_definition is not implemented" end # Sets or removes a NOT NULL constraint on a column. The +null+ flag # indicates whether the value can be +NULL+. For example # # change_column_null(:users, :nickname, false) # # says nicknames cannot be +NULL+ (adds the constraint), whereas # # change_column_null(:users, :nickname, true) # # allows them to be +NULL+ (drops the constraint). # # The method accepts an optional fourth argument to replace existing # NULLs with some other value. Use that one when enabling the # constraint if needed, since otherwise those rows would not be valid. # # Please note the fourth argument does not set a column's default. def change_column_null(table_name, column_name, null, default = nil) raise NotImplementedError, "change_column_null is not implemented" end # Renames a column. # # rename_column(:suppliers, :description, :name) # def rename_column(table_name, column_name, new_column_name) raise NotImplementedError, "rename_column is not implemented" end # Adds a new index to the table. +column_name+ can be a single Symbol, or # an Array of Symbols. # # The index will be named after the table and the column name(s), unless # you pass :name as an option. # # ====== Creating a simple index # # add_index(:suppliers, :name) # # generates: # # CREATE INDEX index_suppliers_on_name ON suppliers(name) # # ====== Creating a index which already exists # # add_index(:suppliers, :name, if_not_exists: true) # # generates: # # CREATE INDEX IF NOT EXISTS index_suppliers_on_name ON suppliers(name) # # Note: Not supported by MySQL. # # ====== Creating a unique index # # add_index(:accounts, [:branch_id, :party_id], unique: true) # # generates: # # CREATE UNIQUE INDEX index_accounts_on_branch_id_and_party_id ON accounts(branch_id, party_id) # # ====== Creating a named index # # 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) # # generates: # # CREATE INDEX by_name ON accounts(name(10)) # # ====== Creating an index with specific key lengths for multiple keys # # 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: only supported by MySQL # # ====== Creating an index with a sort order (desc or asc, asc is the default) # # add_index(:accounts, [:branch_id, :party_id, :surname], name: 'by_branch_desc_party', 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 only supports index order from 8.0.1 onwards (earlier versions accepted the syntax but ignored it). # # ====== Creating a partial index # # 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: Partial indexes are only supported for PostgreSQL and SQLite. # # ====== Creating an index that includes additional columns # # add_index(:accounts, :branch_id, include: :party_id) # # generates: # # CREATE INDEX index_accounts_on_branch_id ON accounts USING btree(branch_id) INCLUDE (party_id) # # Note: only supported by PostgreSQL. # # ====== Creating an index with a specific method # # add_index(:developers, :name, using: 'btree') # # generates: # # CREATE INDEX index_developers_on_name ON developers USING btree (name) -- PostgreSQL # CREATE INDEX index_developers_on_name USING btree ON developers (name) -- MySQL # # Note: only supported by PostgreSQL and MySQL # # ====== Creating an index with a specific operator class # # add_index(:developers, :name, using: 'gist', opclass: :gist_trgm_ops) # # CREATE INDEX developers_on_name ON developers USING gist (name gist_trgm_ops) -- PostgreSQL # # add_index(:developers, [:name, :city], using: 'gist', opclass: { city: :gist_trgm_ops }) # # CREATE INDEX developers_on_name_and_city ON developers USING gist (name, city gist_trgm_ops) -- PostgreSQL # # add_index(:developers, [:name, :city], using: 'gist', opclass: :gist_trgm_ops) # # CREATE INDEX developers_on_name_and_city ON developers USING gist (name gist_trgm_ops, city gist_trgm_ops) -- PostgreSQL # # Note: only supported by PostgreSQL # # ====== Creating an index with a specific type # # add_index(:developers, :name, type: :fulltext) # # generates: # # CREATE FULLTEXT INDEX index_developers_on_name ON developers (name) -- MySQL # # Note: only supported by MySQL. # # ====== Creating an index with a specific algorithm # # add_index(:developers, :name, algorithm: :concurrently) # # CREATE INDEX CONCURRENTLY developers_on_name on developers (name) # # Note: only supported by PostgreSQL. # # Concurrently adding an index is not supported in a transaction. # # For more information see the {"Transactional Migrations" section}[rdoc-ref:Migration]. def add_index(table_name, column_name, **options) create_index = build_create_index_definition(table_name, column_name, **options) execute schema_creation.accept(create_index) end # Builds a CreateIndexDefinition object. # # This definition object contains information about the index that would be created # if the same arguments were passed to #add_index. See #add_index for information about # passing a +table_name+, +column_name+, and other additional options that can be passed. def build_create_index_definition(table_name, column_name, **options) # :nodoc: index, algorithm, if_not_exists = add_index_options(table_name, column_name, **options) CreateIndexDefinition.new(index, algorithm, if_not_exists) end # Removes the given index from the table. # # Removes the index on +branch_id+ in the +accounts+ table if exactly one such index exists. # # remove_index :accounts, :branch_id # # Removes the index on +branch_id+ in the +accounts+ table if exactly one such index exists. # # remove_index :accounts, column: :branch_id # # Removes the index on +branch_id+ and +party_id+ in the +accounts+ table if exactly one such index exists. # # remove_index :accounts, column: [:branch_id, :party_id] # # Removes the index named +by_branch_party+ in the +accounts+ table. # # remove_index :accounts, name: :by_branch_party # # Removes the index on +branch_id+ named +by_branch_party+ in the +accounts+ table. # # remove_index :accounts, :branch_id, name: :by_branch_party # # Checks if the index exists before trying to remove it. Will silently ignore indexes that # don't exist. # # remove_index :accounts, if_exists: true # # Removes the index named +by_branch_party+ in the +accounts+ table +concurrently+. # # remove_index :accounts, name: :by_branch_party, algorithm: :concurrently # # Note: only supported by PostgreSQL. # # Concurrently removing an index is not supported in a transaction. # # For more information see the {"Transactional Migrations" section}[rdoc-ref:Migration]. def remove_index(table_name, column_name = nil, **options) return if options[:if_exists] && !index_exists?(table_name, column_name, **options) index_name = index_name_for_remove(table_name, column_name, options) execute "DROP INDEX #{quote_column_name(index_name)} ON #{quote_table_name(table_name)}" end # Renames an index. # # 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) old_name = old_name.to_s new_name = new_name.to_s validate_index_length!(table_name, new_name) # this is a naive implementation; some DBs may support this more efficiently (PostgreSQL, for instance) old_index_def = indexes(table_name).detect { |i| i.name == old_name } return unless old_index_def add_index(table_name, old_index_def.columns, name: new_name, unique: old_index_def.unique) remove_index(table_name, name: old_name) end def index_name(table_name, options) # :nodoc: if Hash === options if options[:column] generate_index_name(table_name, options[:column]) elsif options[:name] options[:name] else raise ArgumentError, "You must specify the index name" end else index_name(table_name, index_name_options(options)) end end # Verifies the existence of an index with a given name. def index_name_exists?(table_name, index_name) index_name = index_name.to_s indexes(table_name).detect { |i| i.name == index_name } end # Adds a reference. The reference column is a bigint by default, # the :type option can be used to specify a different type. # Optionally adds a +_type+ column, if :polymorphic option is provided. # #add_reference and #add_belongs_to are acceptable. # # The +options+ hash can include the following keys: # [:type] # The reference column type. Defaults to +:bigint+. # [:index] # Add an appropriate index. Defaults to true. # See #add_index for usage of this option. # [:foreign_key] # Add an appropriate foreign key constraint. Defaults to false, pass true # to add. In case the join table can't be inferred from the association # pass :to_table with the appropriate table name. # [:polymorphic] # Whether an additional +_type+ column should be added. Defaults to false. # [:null] # Whether the column allows nulls. Defaults to true. # # ====== Create a user_id bigint column without an index # # add_reference(:products, :user, index: false) # # ====== Create a user_id string column # # add_reference(:products, :user, type: :string) # # ====== Create supplier_id, supplier_type columns # # add_reference(:products, :supplier, polymorphic: true) # # ====== Create a supplier_id column with a unique index # # add_reference(:products, :supplier, index: { unique: true }) # # ====== Create a supplier_id column with a named index # # add_reference(:products, :supplier, index: { name: "my_supplier_index" }) # # ====== Create a supplier_id column and appropriate foreign key # # add_reference(:products, :supplier, foreign_key: true) # # ====== Create a supplier_id column and a foreign key to the firms table # # add_reference(:products, :supplier, foreign_key: { to_table: :firms }) # def add_reference(table_name, ref_name, **options) ReferenceDefinition.new(ref_name, **options).add(table_name, self) end alias :add_belongs_to :add_reference # Removes the reference(s). Also removes a +type+ column if one exists. # #remove_reference and #remove_belongs_to are acceptable. # # ====== Remove the reference # # remove_reference(:products, :user, index: false) # # ====== Remove polymorphic reference # # remove_reference(:products, :supplier, polymorphic: true) # # ====== Remove the reference with a foreign key # # remove_reference(:products, :user, foreign_key: true) # def remove_reference(table_name, ref_name, foreign_key: false, polymorphic: false, **options) conditional_options = options.slice(:if_exists, :if_not_exists) if foreign_key reference_name = Base.pluralize_table_names ? ref_name.to_s.pluralize : ref_name if foreign_key.is_a?(Hash) foreign_key_options = foreign_key.merge(conditional_options) else foreign_key_options = { to_table: reference_name, **conditional_options } end foreign_key_options[:column] ||= "#{ref_name}_id" remove_foreign_key(table_name, **foreign_key_options) end remove_column(table_name, "#{ref_name}_id", **conditional_options) remove_column(table_name, "#{ref_name}_type", **conditional_options) if polymorphic end alias :remove_belongs_to :remove_reference # Returns an array of foreign keys for the given table. # The foreign keys are represented as ForeignKeyDefinition objects. def foreign_keys(table_name) raise NotImplementedError, "foreign_keys is not implemented" end # Adds a new foreign key. +from_table+ is the table with the key column, # +to_table+ contains the referenced primary key. # # The foreign key will be named after the following pattern: fk_rails_. # +identifier+ is a 10 character long string which is deterministically generated from the # +from_table+ and +column+. A custom name can be specified with the :name option. # # ====== Creating a simple foreign key # # add_foreign_key :articles, :authors # # generates: # # ALTER TABLE "articles" ADD CONSTRAINT fk_rails_e74ce85cbc FOREIGN KEY ("author_id") REFERENCES "authors" ("id") # # ====== Creating a foreign key, ignoring method call if the foreign key exists # # add_foreign_key(:articles, :authors, if_not_exists: true) # # ====== Creating a foreign key on a specific column # # add_foreign_key :articles, :users, column: :author_id, primary_key: "lng_id" # # generates: # # ALTER TABLE "articles" ADD CONSTRAINT fk_rails_58ca3d3a82 FOREIGN KEY ("author_id") REFERENCES "users" ("lng_id") # # ====== Creating a composite foreign key # # Assuming "carts" table has "(shop_id, user_id)" as a primary key. # # add_foreign_key :orders, :carts, primary_key: [:shop_id, :user_id] # # generates: # # ALTER TABLE "orders" ADD CONSTRAINT fk_rails_6f5e4cb3a4 FOREIGN KEY ("cart_shop_id", "cart_user_id") REFERENCES "carts" ("shop_id", "user_id") # # ====== Creating a cascading foreign key # # add_foreign_key :articles, :authors, on_delete: :cascade # # generates: # # ALTER TABLE "articles" ADD CONSTRAINT fk_rails_e74ce85cbc FOREIGN KEY ("author_id") REFERENCES "authors" ("id") ON DELETE CASCADE # # The +options+ hash can include the following keys: # [:column] # The foreign key column name on +from_table+. Defaults to to_table.singularize + "_id". # Pass an array to create a composite foreign key. # [:primary_key] # The primary key column name on +to_table+. Defaults to +id+. # Pass an array to create a composite foreign key. # [:name] # The constraint name. Defaults to fk_rails_. # [:on_delete] # Action that happens ON DELETE. Valid values are +:nullify+, +:cascade+, and +:restrict+ # [:on_update] # Action that happens ON UPDATE. Valid values are +:nullify+, +:cascade+, and +:restrict+ # [:if_not_exists] # Specifies if the foreign key already exists to not try to re-add it. This will avoid # duplicate column errors. # [:validate] # (PostgreSQL only) Specify whether or not the constraint should be validated. Defaults to +true+. # [:deferrable] # (PostgreSQL only) Specify whether or not the foreign key should be deferrable. Valid values are booleans or # +:deferred+ or +:immediate+ to specify the default behavior. Defaults to +false+. def add_foreign_key(from_table, to_table, **options) return unless use_foreign_keys? return if options[:if_not_exists] == true && foreign_key_exists?(from_table, to_table, **options.slice(:column)) options = foreign_key_options(from_table, to_table, options) at = create_alter_table from_table at.add_foreign_key to_table, options execute schema_creation.accept(at) end # Removes the given foreign key from the table. Any option parameters provided # will be used to re-add the foreign key in case of a migration rollback. # It is recommended that you provide any options used when creating the foreign # key so that the migration can be reverted properly. # # Removes the foreign key on +accounts.branch_id+. # # remove_foreign_key :accounts, :branches # # Removes the foreign key on +accounts.owner_id+. # # remove_foreign_key :accounts, column: :owner_id # # Removes the foreign key on +accounts.owner_id+. # # remove_foreign_key :accounts, to_table: :owners # # Removes the foreign key named +special_fk_name+ on the +accounts+ table. # # remove_foreign_key :accounts, name: :special_fk_name # # Checks if the foreign key exists before trying to remove it. Will silently ignore indexes that # don't exist. # # remove_foreign_key :accounts, :branches, if_exists: true # # The +options+ hash accepts the same keys as SchemaStatements#add_foreign_key # with an addition of # [:to_table] # The name of the table that contains the referenced primary key. def remove_foreign_key(from_table, to_table = nil, **options) return unless use_foreign_keys? return if options.delete(:if_exists) == true && !foreign_key_exists?(from_table, to_table) fk_name_to_delete = foreign_key_for!(from_table, to_table: to_table, **options).name at = create_alter_table from_table at.drop_foreign_key fk_name_to_delete execute schema_creation.accept(at) end # Checks to see if a foreign key exists on a table for a given foreign key definition. # # # Checks to see if a foreign key exists. # foreign_key_exists?(:accounts, :branches) # # # Checks to see if a foreign key on a specified column exists. # foreign_key_exists?(:accounts, column: :owner_id) # # # Checks to see if a foreign key with a custom name exists. # foreign_key_exists?(:accounts, name: "special_fk_name") # def foreign_key_exists?(from_table, to_table = nil, **options) foreign_key_for(from_table, to_table: to_table, **options).present? end def foreign_key_column_for(table_name, column_name) # :nodoc: name = strip_table_name_prefix_and_suffix(table_name) "#{name.singularize}_#{column_name}" end def foreign_key_options(from_table, to_table, options) # :nodoc: options = options.dup if options[:primary_key].is_a?(Array) options[:column] ||= options[:primary_key].map do |pk_column| foreign_key_column_for(to_table, pk_column) end else options[:column] ||= foreign_key_column_for(to_table, "id") end options[:name] ||= foreign_key_name(from_table, options) if options[:column].is_a?(Array) || options[:primary_key].is_a?(Array) if Array(options[:primary_key]).size != Array(options[:column]).size raise ArgumentError, <<~MSG.squish For composite primary keys, specify :column and :primary_key, where :column must reference all the :primary_key columns from #{to_table.inspect} MSG end end options end # Returns an array of check constraints for the given table. # The check constraints are represented as CheckConstraintDefinition objects. def check_constraints(table_name) raise NotImplementedError end # Adds a new check constraint to the table. +expression+ is a String # representation of verifiable boolean condition. # # add_check_constraint :products, "price > 0", name: "price_check" # # generates: # # ALTER TABLE "products" ADD CONSTRAINT price_check CHECK (price > 0) # # The +options+ hash can include the following keys: # [:name] # The constraint name. Defaults to chk_rails_. # [:if_not_exists] # Silently ignore if the constraint already exists, rather than raise an error. # [:validate] # (PostgreSQL only) Specify whether or not the constraint should be validated. Defaults to +true+. def add_check_constraint(table_name, expression, if_not_exists: false, **options) return unless supports_check_constraints? options = check_constraint_options(table_name, expression, options) return if if_not_exists && check_constraint_exists?(table_name, **options) at = create_alter_table(table_name) at.add_check_constraint(expression, options) execute schema_creation.accept(at) end def check_constraint_options(table_name, expression, options) # :nodoc: options = options.dup options[:name] ||= check_constraint_name(table_name, expression: expression, **options) options end # Removes the given check constraint from the table. Removing a check constraint # that does not exist will raise an error. # # remove_check_constraint :products, name: "price_check" # # To silently ignore a non-existent check constraint rather than raise an error, # use the +if_exists+ option. # # remove_check_constraint :products, name: "price_check", if_exists: true # # The +expression+ parameter will be ignored if present. It can be helpful # to provide this in a migration's +change+ method so it can be reverted. # In that case, +expression+ will be used by #add_check_constraint. def remove_check_constraint(table_name, expression = nil, if_exists: false, **options) return unless supports_check_constraints? return if if_exists && !check_constraint_exists?(table_name, **options) chk_name_to_delete = check_constraint_for!(table_name, expression: expression, **options).name at = create_alter_table(table_name) at.drop_check_constraint(chk_name_to_delete) execute schema_creation.accept(at) end # Checks to see if a check constraint exists on a table for a given check constraint definition. # # check_constraint_exists?(:products, name: "price_check") # def check_constraint_exists?(table_name, **options) if !options.key?(:name) && !options.key?(:expression) raise ArgumentError, "At least one of :name or :expression must be supplied" end check_constraint_for(table_name, **options).present? end def dump_schema_information # :nodoc: versions = schema_migration.versions insert_versions_sql(versions) if versions.any? end def internal_string_options_for_primary_key # :nodoc: { primary_key: true } end def assume_migrated_upto_version(version) version = version.to_i sm_table = quote_table_name(schema_migration.table_name) migrated = migration_context.get_all_versions versions = migration_context.migrations.map(&:version) unless migrated.include?(version) execute "INSERT INTO #{sm_table} (version) VALUES (#{quote(version)})" end inserting = (versions - migrated).select { |v| v < version } if inserting.any? if (duplicate = inserting.detect { |v| inserting.count(v) > 1 }) raise "Duplicate migration #{duplicate}. Please renumber your migrations to resolve the conflict." end execute insert_versions_sql(inserting) end end def type_to_sql(type, limit: nil, precision: nil, scale: nil, **) # :nodoc: type = type.to_sym if type if native = native_database_types[type] column_type_sql = (native.is_a?(Hash) ? native[:name] : native).dup if type == :decimal # ignore limit, use precision and scale scale ||= native[:scale] if precision ||= native[:precision] if scale column_type_sql << "(#{precision},#{scale})" else column_type_sql << "(#{precision})" end elsif scale raise ArgumentError, "Error adding decimal column: precision cannot be empty if scale is specified" end elsif [:datetime, :timestamp, :time, :interval].include?(type) && precision ||= native[:precision] if (0..6) === precision column_type_sql << "(#{precision})" else raise ArgumentError, "No #{native[:name]} type has precision of #{precision}. The allowed range of precision is from 0 to 6" end elsif (type != :primary_key) && (limit ||= native.is_a?(Hash) && native[:limit]) column_type_sql << "(#{limit})" end column_type_sql else type.to_s end end # Given a set of columns and an ORDER BY clause, returns the columns for a SELECT DISTINCT. # PostgreSQL, MySQL, and Oracle override this for custom DISTINCT syntax - they # require the order columns appear in the SELECT. # # columns_for_distinct("posts.id", ["posts.created_at desc"]) # def columns_for_distinct(columns, orders) # :nodoc: columns end def distinct_relation_for_primary_key(relation) # :nodoc: primary_key_columns = Array(relation.primary_key).map do |column| visitor.compile(relation.table[column]) end values = columns_for_distinct( primary_key_columns, relation.order_values ) limited = relation.reselect(values).distinct! limited_ids = select_rows(limited.arel, "SQL").map do |results| results.last(Array(relation.primary_key).length) # ignores order values for MySQL and Postgres end if limited_ids.empty? relation.none! else relation.where!(**Array(relation.primary_key).zip(limited_ids.transpose).to_h) end relation.limit_value = relation.offset_value = nil relation end # Adds timestamps (+created_at+ and +updated_at+) columns to +table_name+. # Additional options (like +:null+) are forwarded to #add_column. # # add_timestamps(:suppliers, null: true) # def add_timestamps(table_name, **options) fragments = add_timestamps_for_alter(table_name, **options) execute "ALTER TABLE #{quote_table_name(table_name)} #{fragments.join(', ')}" end # Removes the timestamp columns (+created_at+ and +updated_at+) from the table definition. # # remove_timestamps(:suppliers) # def remove_timestamps(table_name, **options) remove_columns table_name, :updated_at, :created_at end def update_table_definition(table_name, base) # :nodoc: Table.new(table_name, base) end def add_index_options(table_name, column_name, name: nil, if_not_exists: false, internal: false, **options) # :nodoc: options.assert_valid_keys(:unique, :length, :order, :opclass, :where, :type, :using, :comment, :algorithm, :include, :nulls_not_distinct) column_names = index_column_names(column_name) index_name = name&.to_s index_name ||= index_name(table_name, column_names) validate_index_length!(table_name, index_name, internal) index = IndexDefinition.new( table_name, index_name, options[:unique], column_names, lengths: options[:length] || {}, orders: options[:order] || {}, opclasses: options[:opclass] || {}, where: options[:where], type: options[:type], using: options[:using], include: options[:include], nulls_not_distinct: options[:nulls_not_distinct], comment: options[:comment] ) [index, index_algorithm(options[:algorithm]), if_not_exists] end def index_algorithm(algorithm) # :nodoc: index_algorithms.fetch(algorithm) do raise ArgumentError, "Algorithm must be one of the following: #{index_algorithms.keys.map(&:inspect).join(', ')}" end if algorithm end def quoted_columns_for_index(column_names, options) # :nodoc: quoted_columns = column_names.each_with_object({}) do |name, result| result[name.to_sym] = quote_column_name(name).dup end add_options_for_index_columns(quoted_columns, **options).values.join(", ") end def options_include_default?(options) options.include?(:default) && !(options[:null] == false && options[:default].nil?) end # Changes the comment for a table or removes it if +nil+. # # Passing a hash containing +:from+ and +:to+ will make this change # reversible in migration: # # change_table_comment(:posts, from: "old_comment", to: "new_comment") def change_table_comment(table_name, comment_or_changes) raise NotImplementedError, "#{self.class} does not support changing table comments" end # Changes the comment for a column or removes it if +nil+. # # Passing a hash containing +:from+ and +:to+ will make this change # reversible in migration: # # change_column_comment(:posts, :state, from: "old_comment", to: "new_comment") def change_column_comment(table_name, column_name, comment_or_changes) raise NotImplementedError, "#{self.class} does not support changing column comments" end def create_schema_dumper(options) # :nodoc: SchemaDumper.create(self, options) end def use_foreign_keys? supports_foreign_keys? && foreign_keys_enabled? end # Returns an instance of SchemaCreation, which can be used to visit a schema definition # object and return DDL. def schema_creation # :nodoc: SchemaCreation.new(self) end def bulk_change_table(table_name, operations) # :nodoc: sql_fragments = [] non_combinable_operations = [] operations.each do |command, args| table, arguments = args.shift, args method = :"#{command}_for_alter" if respond_to?(method, true) sqls, procs = Array(send(method, table, *arguments)).partition { |v| v.is_a?(String) } sql_fragments.concat(sqls) non_combinable_operations.concat(procs) else execute "ALTER TABLE #{quote_table_name(table_name)} #{sql_fragments.join(", ")}" unless sql_fragments.empty? non_combinable_operations.each(&:call) sql_fragments = [] non_combinable_operations = [] send(command, table, *arguments) end end execute "ALTER TABLE #{quote_table_name(table_name)} #{sql_fragments.join(", ")}" unless sql_fragments.empty? non_combinable_operations.each(&:call) end def valid_table_definition_options # :nodoc: [:temporary, :if_not_exists, :options, :as, :comment, :charset, :collation] end def valid_column_definition_options # :nodoc: ColumnDefinition::OPTION_NAMES end def valid_primary_key_options # :nodoc: [:limit, :default, :precision] end # Returns the maximum length of an index name in bytes. def max_index_name_size 62 end private def generate_index_name(table_name, column) name = "index_#{table_name}_on_#{Array(column) * '_and_'}" return name if name.bytesize <= max_index_name_size # Fallback to short version, add hash to ensure uniqueness hashed_identifier = "_" + OpenSSL::Digest::SHA256.hexdigest(name).first(10) name = "idx_on_#{Array(column) * '_'}" short_limit = max_index_name_size - hashed_identifier.bytesize short_name = name.mb_chars.limit(short_limit).to_s "#{short_name}#{hashed_identifier}" end def validate_change_column_null_argument!(value) unless value == true || value == false raise ArgumentError, "change_column_null expects a boolean value (true for NULL, false for NOT NULL). Got: #{value.inspect}" end end def column_options_keys [:limit, :precision, :scale, :default, :null, :collation, :comment] end def add_index_sort_order(quoted_columns, **options) orders = options_for_index_columns(options[:order]) quoted_columns.each do |name, column| column << " #{orders[name].upcase}" if orders[name].present? end end def options_for_index_columns(options) if options.is_a?(Hash) options.symbolize_keys else Hash.new { |hash, column| hash[column] = options } end end # Overridden by the MySQL adapter for supporting index lengths and by # the PostgreSQL adapter for supporting operator classes. def add_options_for_index_columns(quoted_columns, **options) if supports_index_sort_order? quoted_columns = add_index_sort_order(quoted_columns, **options) end quoted_columns end def index_name_for_remove(table_name, column_name, options) return options[:name] if can_remove_index_by_name?(column_name, options) checks = [] if !options.key?(:name) && expression_column_name?(column_name) options[:name] = index_name(table_name, column_name) column_names = [] else column_names = index_column_names(column_name || options[:column]) end checks << lambda { |i| i.name == options[:name].to_s } if options.key?(:name) if column_names.present? && !(options.key?(:name) && expression_column_name?(column_names)) checks << lambda { |i| index_name(table_name, i.columns) == index_name(table_name, column_names) } end raise ArgumentError, "No name or columns specified" if checks.none? matching_indexes = indexes(table_name).select { |i| checks.all? { |check| check[i] } } if matching_indexes.count > 1 raise ArgumentError, "Multiple indexes found on #{table_name} columns #{column_names}. " \ "Specify an index name from #{matching_indexes.map(&:name).join(', ')}" elsif matching_indexes.none? raise ArgumentError, "No indexes found on #{table_name} with the options provided." else matching_indexes.first.name end end def rename_table_indexes(table_name, new_name) indexes(new_name).each do |index| generated_index_name = index_name(table_name, column: index.columns) if generated_index_name == index.name rename_index new_name, generated_index_name, index_name(new_name, column: index.columns) end end end def rename_column_indexes(table_name, column_name, new_column_name) column_name, new_column_name = column_name.to_s, new_column_name.to_s indexes(table_name).each do |index| next unless index.columns.include?(new_column_name) old_columns = index.columns.dup old_columns[old_columns.index(new_column_name)] = column_name generated_index_name = index_name(table_name, column: old_columns) if generated_index_name == index.name rename_index table_name, generated_index_name, index_name(table_name, column: index.columns) end end end def create_table_definition(name, **options) TableDefinition.new(self, name, **options) end def create_alter_table(name) AlterTable.new create_table_definition(name) end def validate_create_table_options!(options) unless options[:_skip_validate_options] options .except(:_uses_legacy_table_name, :_skip_validate_options) .assert_valid_keys(valid_table_definition_options, valid_primary_key_options) end end def fetch_type_metadata(sql_type) cast_type = lookup_cast_type(sql_type) SqlTypeMetadata.new( sql_type: sql_type, type: cast_type.type, limit: cast_type.limit, precision: cast_type.precision, scale: cast_type.scale, ) end def index_column_names(column_names) if expression_column_name?(column_names) column_names else Array(column_names) end end def index_name_options(column_names) if expression_column_name?(column_names) column_names = column_names.scan(/\w+/).join("_") end { column: column_names } end # Try to identify whether the given column name is an expression def expression_column_name?(column_name) column_name.is_a?(String) && /\W/.match?(column_name) end def strip_table_name_prefix_and_suffix(table_name) prefix = Base.table_name_prefix suffix = Base.table_name_suffix table_name.to_s =~ /#{prefix}(.+)#{suffix}/ ? $1 : table_name.to_s end def foreign_key_name(table_name, options) options.fetch(:name) do columns = Array(options.fetch(:column)).map(&:to_s) identifier = "#{table_name}_#{columns * '_and_'}_fk" hashed_identifier = OpenSSL::Digest::SHA256.hexdigest(identifier).first(10) "fk_rails_#{hashed_identifier}" end end def foreign_key_for(from_table, **options) return unless use_foreign_keys? foreign_keys(from_table).detect { |fk| fk.defined_for?(**options) } end def foreign_key_for!(from_table, to_table: nil, **options) foreign_key_for(from_table, to_table: to_table, **options) || raise(ArgumentError, "Table '#{from_table}' has no foreign key for #{to_table || options}") end def extract_foreign_key_action(specifier) case specifier when "CASCADE"; :cascade when "SET NULL"; :nullify when "RESTRICT"; :restrict end end def foreign_keys_enabled? @config.fetch(:foreign_keys, true) end def check_constraint_name(table_name, **options) options.fetch(:name) do expression = options.fetch(:expression) identifier = "#{table_name}_#{expression}_chk" hashed_identifier = OpenSSL::Digest::SHA256.hexdigest(identifier).first(10) "chk_rails_#{hashed_identifier}" end end def check_constraint_for(table_name, **options) return unless supports_check_constraints? chk_name = check_constraint_name(table_name, **options) check_constraints(table_name).detect { |chk| chk.defined_for?(name: chk_name, **options) } end def check_constraint_for!(table_name, expression: nil, **options) check_constraint_for(table_name, expression: expression, **options) || raise(ArgumentError, "Table '#{table_name}' has no check constraint for #{expression || options}") end def validate_index_length!(table_name, new_name, internal = false) if new_name.length > index_name_length raise ArgumentError, "Index name '#{new_name}' on table '#{table_name}' is too long; the limit is #{index_name_length} characters" end end def validate_table_length!(table_name) if table_name.length > table_name_length raise ArgumentError, "Table name '#{table_name}' is too long; the limit is #{table_name_length} characters" end end def extract_new_default_value(default_or_changes) if default_or_changes.is_a?(Hash) && default_or_changes.has_key?(:from) && default_or_changes.has_key?(:to) default_or_changes[:to] else default_or_changes end end alias :extract_new_comment_value :extract_new_default_value def can_remove_index_by_name?(column_name, options) column_name.nil? && options.key?(:name) && options.except(:name, :algorithm).empty? end def reference_name_for_table(table_name) table_name.to_s.singularize end def add_column_for_alter(table_name, column_name, type, **options) td = create_table_definition(table_name) cd = td.new_column_definition(column_name, type, **options) schema_creation.accept(AddColumnDefinition.new(cd)) end def change_column_default_for_alter(table_name, column_name, default_or_changes) cd = build_change_column_default_definition(table_name, column_name, default_or_changes) schema_creation.accept(cd) end def rename_column_sql(table_name, column_name, new_column_name) "RENAME COLUMN #{quote_column_name(column_name)} TO #{quote_column_name(new_column_name)}" end def remove_column_for_alter(table_name, column_name, type = nil, **options) "DROP COLUMN #{quote_column_name(column_name)}" end def remove_columns_for_alter(table_name, *column_names, **options) column_names.map { |column_name| remove_column_for_alter(table_name, column_name) } end def add_timestamps_for_alter(table_name, **options) options[:null] = false if options[:null].nil? if !options.key?(:precision) && supports_datetime_with_precision? options[:precision] = 6 end [ add_column_for_alter(table_name, :created_at, :datetime, **options), add_column_for_alter(table_name, :updated_at, :datetime, **options) ] end def remove_timestamps_for_alter(table_name, **options) remove_columns_for_alter(table_name, :updated_at, :created_at) end def insert_versions_sql(versions) sm_table = quote_table_name(schema_migration.table_name) if versions.is_a?(Array) sql = +"INSERT INTO #{sm_table} (version) VALUES\n" sql << versions.reverse.map { |v| "(#{quote(v)})" }.join(",\n") sql << ";" sql else "INSERT INTO #{sm_table} (version) VALUES (#{quote(versions)});" end end def data_source_sql(name = nil, type: nil) raise NotImplementedError end def quoted_scope(name = nil, type: nil) raise NotImplementedError end end end end