require 'active_support/core_ext/string/strip' module ActiveRecord module ConnectionAdapters class AbstractAdapter class SchemaCreation # :nodoc: def initialize(conn) @conn = conn @cache = {} end def accept(o) m = @cache[o.class] ||= "visit_#{o.class.name.split('::').last}" send m, o end delegate :quote_column_name, :quote_table_name, :quote_default_expression, :type_to_sql, :options_include_default?, :supports_indexes_in_create?, :supports_foreign_keys?, :foreign_key_options, to: :@conn private :quote_column_name, :quote_table_name, :quote_default_expression, :type_to_sql, :options_include_default?, :supports_indexes_in_create?, :supports_foreign_keys?, :foreign_key_options private def visit_AlterTable(o) sql = "ALTER TABLE #{quote_table_name(o.name)} " sql << o.adds.map { |col| accept col }.join(' ') sql << o.foreign_key_adds.map { |fk| visit_AddForeignKey fk }.join(' ') sql << o.foreign_key_drops.map { |fk| visit_DropForeignKey fk }.join(' ') end def visit_ColumnDefinition(o) o.sql_type ||= type_to_sql(o.type, o.limit, o.precision, o.scale) column_sql = "#{quote_column_name(o.name)} #{o.sql_type}" add_column_options!(column_sql, column_options(o)) unless o.type == :primary_key column_sql end def visit_AddColumnDefinition(o) "ADD #{accept(o.column)}" end def visit_TableDefinition(o) create_sql = "CREATE#{' TEMPORARY' if o.temporary} TABLE #{quote_table_name(o.name)} " statements = o.columns.map { |c| accept c } statements << accept(o.primary_keys) if o.primary_keys if supports_indexes_in_create? statements.concat(o.indexes.map { |column_name, options| index_in_create(o.name, column_name, options) }) end if supports_foreign_keys? statements.concat(o.foreign_keys.map { |to_table, options| foreign_key_in_create(o.name, to_table, options) }) end create_sql << "(#{statements.join(', ')}) " if statements.present? create_sql << "#{o.options}" create_sql << " AS #{@conn.to_sql(o.as)}" if o.as create_sql end def visit_PrimaryKeyDefinition(o) "PRIMARY KEY (#{o.name.join(', ')})" end def visit_ForeignKeyDefinition(o) sql = <<-SQL.strip_heredoc CONSTRAINT #{quote_column_name(o.name)} FOREIGN KEY (#{quote_column_name(o.column)}) REFERENCES #{quote_table_name(o.to_table)} (#{quote_column_name(o.primary_key)}) SQL sql << " #{action_sql('DELETE', o.on_delete)}" if o.on_delete sql << " #{action_sql('UPDATE', o.on_update)}" if o.on_update sql end def visit_AddForeignKey(o) "ADD #{accept(o)}" end def visit_DropForeignKey(name) "DROP CONSTRAINT #{quote_column_name(name)}" end def column_options(o) column_options = {} column_options[:null] = o.null unless o.null.nil? column_options[:default] = o.default unless o.default.nil? column_options[:column] = o column_options[:first] = o.first column_options[:after] = o.after column_options[:auto_increment] = o.auto_increment column_options[:primary_key] = o.primary_key column_options[:collation] = o.collation column_options end def add_column_options!(sql, options) sql << " DEFAULT #{quote_default_expression(options[:default], options[:column])}" if options_include_default?(options) # must explicitly check for :null to allow change_column to work on migrations if options[:null] == false sql << " NOT NULL" end if options[:auto_increment] == true sql << " AUTO_INCREMENT" end if options[:primary_key] == true sql << " PRIMARY KEY" end sql end def foreign_key_in_create(from_table, to_table, options) options = foreign_key_options(from_table, to_table, options) accept ForeignKeyDefinition.new(from_table, to_table, options) end def action_sql(action, dependency) case dependency when :nullify then "ON #{action} SET NULL" when :cascade then "ON #{action} CASCADE" when :restrict then "ON #{action} RESTRICT" else raise ArgumentError, <<-MSG.strip_heredoc '#{dependency}' is not supported for :on_update or :on_delete. Supported values are: :nullify, :cascade, :restrict MSG end end end end end end