# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 588 def primary_key(table) pk_and_sequence = pk_and_sequence_for(table) pk_and_sequence && pk_and_sequence.first end
class ActiveRecord::ConnectionAdapters::AbstractMysqlAdapter
Constants
- INDEX_TYPES
- INDEX_USINGS
- LOST_CONNECTION_ERROR_MESSAGES
- NATIVE_DATABASE_TYPES
- QUOTED_FALSE
Public Class Methods
By default, the MysqlAdapter will consider
all columns of type tinyint(1)
as boolean. If you wish to
disable this emulation (which was the default behavior in versions 0.13.1
and earlier) you can add the following line to your application.rb file:
ActiveRecord::ConnectionAdapters::Mysql[2]Adapter.emulate_booleans = false
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 141 class_attribute :emulate_booleans
FIXME: Make the first parameter more similar for the two adapters
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 175 def initialize(connection, logger, connection_options, config) super(connection, logger) @connection_options, @config = connection_options, config @quoted_column_names, @quoted_table_names = {}, {} if self.class.type_cast_config_to_boolean(config.fetch(:prepared_statements) { true }) @prepared_statements = true @visitor = Arel::Visitors::MySQL.new self else @visitor = unprepared_visitor end end
Public Instance Methods
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 560 def add_column_position!(sql, options) if options[:first] sql << " FIRST" elsif options[:after] sql << " AFTER #{quote_column_name(options[:after])}" end end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 318 def begin_db_transaction execute "BEGIN" end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 322 def begin_isolated_db_transaction(isolation) execute "SET TRANSACTION ISOLATION LEVEL #{transaction_isolation_levels.fetch(isolation)}" begin_db_transaction end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 597 def case_insensitive_comparison(table, attribute, column, value) if column.case_sensitive? super else table[attribute].eq(value) end end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 593 def case_sensitive_modifier(node) Arel::Nodes::Bin.new(node) end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 499 def change_column_default(table_name, column_name, default) column = column_for(table_name, column_name) change_column table_name, column_name, column.sql_type, :default => default end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 504 def change_column_null(table_name, column_name, null, default = nil) column = column_for(table_name, column_name) unless null || default.nil? execute("UPDATE #{quote_table_name(table_name)} SET #{quote_column_name(column_name)}=#{quote(default)} WHERE #{quote_column_name(column_name)} IS NULL") end change_column table_name, column_name, column.sql_type, :null => null end
Returns the database character set.
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 390 def charset show_variable 'character_set_database' end
Returns the database collation strategy.
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 395 def collation show_variable 'collation_database' end
Create a new MySQL database with optional :charset
and
:collation
. Charset defaults to utf8.
Example:
create_database 'charset_test', charset: 'latin1', collation: 'latin1_bin' create_database 'matt_development' create_database 'matt_development', charset: :big5
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 369 def create_database(name, options = {}) if options[:collation] execute "CREATE DATABASE `#{name}` DEFAULT CHARACTER SET `#{options[:charset] || 'utf8'}` COLLATE `#{options[:collation]}`" else execute "CREATE DATABASE `#{name}` DEFAULT CHARACTER SET `#{options[:charset] || 'utf8'}`" end end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 385 def current_database select_value 'SELECT DATABASE() as db' end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 487 def drop_table(table_name, options = {}) execute "DROP#{' TEMPORARY' if options[:temporary]} TABLE #{quote_table_name(table_name)}" end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 347 def empty_insert_statement_value "VALUES ()" end
Executes the SQL statement in the context of this connection.
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 302 def execute(sql, name = nil) log(sql, name) { @connection.query(sql) } end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 234 def index_algorithms { default: 'ALGORITHM = DEFAULT', copy: 'ALGORITHM = COPY', inplace: 'ALGORITHM = INPLACE' } end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 605 def limited_update_conditions(where_sql, quoted_table_name, quoted_primary_key) where_sql end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 230 def native_database_types NATIVE_DATABASE_TYPES end
Returns a table's primary key and belonging sequence.
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 575 def pk_and_sequence_for(table) execute_and_free("SHOW CREATE TABLE #{quote_table_name(table)}", 'SCHEMA') do |result| create_table = each_hash(result).first[:"Create Table"] if create_table.to_s =~ /PRIMARY KEY\s+(?:USING\s+\w+\s+)?\((.+)\)/ keys = $1.split(",").map { |key| key.delete('`"') } keys.length == 1 ? [keys.first, nil] : nil else nil end end end
Returns just a table's primary key
QUOTING ==================================================
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 259 def quote(value, column = nil) if value.kind_of?(String) && column && column.type == :binary s = value.unpack("H*")[0] "x'#{s}'" elsif value.kind_of?(BigDecimal) value.to_s("F") else super end end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 282 def quoted_false QUOTED_FALSE end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 278 def quoted_true QUOTED_TRUE end
Drops the database specified on the name
attribute and creates
it again using the provided options
.
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 355 def recreate_database(name, options = {}) drop_database(name) sql = create_database(name, options) reconnect! sql end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 491 def rename_index(table_name, old_name, new_name) if (version[0] == 5 && version[1] >= 7) || version[0] >= 6 execute "ALTER TABLE #{quote_table_name(table_name)} RENAME INDEX #{quote_table_name(old_name)} TO #{quote_table_name(new_name)}" else super end end
Renames a table.
Example:
rename_table('octopuses', 'octopi')
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 482 def rename_table(table_name, new_name) execute "RENAME TABLE #{quote_table_name(table_name)} TO #{quote_table_name(new_name)}" rename_table_indexes(table_name, new_name) end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 34 def schema_creation SchemaCreation.new self end
SHOW VARIABLES LIKE 'name'
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 569 def show_variable(name) variables = select_all("SHOW VARIABLES LIKE '#{name}'", 'SCHEMA') variables.first['Value'] unless variables.empty? end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 609 def strict_mode? self.class.type_cast_config_to_boolean(@config.fetch(:strict, true)) end
Technically MySQL allows to create indexes with the sort order syntax but at the moment (5.5) it doesn't yet implement them
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 207 def supports_index_sort_order? true end
Returns true, since this connection adapter supports migrations.
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 193 def supports_migrations? true end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 197 def supports_primary_key? true end
MySQL 4 technically support transaction isolation, but it is affected by a bug where the transaction level gets persisted for the whole session:
bugs.mysql.com/bug.php?id=39170
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 226 def supports_transaction_isolation? version[0] >= 5 end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 409 def table_exists?(name) return false unless name return true if tables(nil, nil, name).any? name = name.to_s schema, table = name.split('.', 2) unless table # A table was provided without a schema table = schema schema = nil end tables(nil, schema, table).any? end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 211 def type_cast(value, column) case value when TrueClass 1 when FalseClass 0 else super end end
Maps logical Rails types to MySQL-specific data types.
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 529 def type_to_sql(type, limit = nil, precision = nil, scale = nil) case type.to_s when 'binary' case limit when 0..0xfff; "varbinary(#{limit})" when nil; "blob" when 0x1000..0xffffffff; "blob(#{limit})" else raise(ActiveRecordError, "No binary type has character length #{limit}") end when 'integer' case limit when 1; 'tinyint' when 2; 'smallint' when 3; 'mediumint' when nil, 4, 11; 'int(11)' # compatibility with MySQL default when 5..8; 'bigint' else raise(ActiveRecordError, "No integer type has byte size #{limit}") end when 'text' case limit when 0..0xff; 'tinytext' when nil, 0x100..0xffff; 'text' when 0x10000..0xffffff; 'mediumtext' when 0x1000000..0xffffffff; 'longtext' else raise(ActiveRecordError, "No text type has character length #{limit}") end else super end end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 613 def valid_type?(type) !native_database_types[type].nil? end
Protected Instance Methods
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 666 def add_column_sql(table_name, column_name, type, options = {}) td = create_table_definition table_name, options[:temporary], options[:options] cd = td.new_column_definition(column_name, type, options) schema_creation.visit_AddColumn cd end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 630 def add_index_length(option_strings, column_names, options = {}) if options.is_a?(Hash) && length = options[:length] case length when Hash column_names.each {|name| option_strings[name] += "(#{length[name]})" if length.has_key?(name) && length[name].present?} when Fixnum column_names.each {|name| option_strings[name] += "(#{length})"} end end return option_strings end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 710 def add_index_sql(table_name, column_name, options = {}) index_name, index_type, index_columns = add_index_options(table_name, column_name, options) "ADD #{index_type} INDEX #{index_name} (#{index_columns})" end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 720 def add_timestamps_sql(table_name) [add_column_sql(table_name, :created_at, :datetime), add_column_sql(table_name, :updated_at, :datetime)] end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 672 def change_column_sql(table_name, column_name, type, options = {}) column = column_for(table_name, column_name) unless options_include_default?(options) options[:default] = column.default end unless options.has_key?(:null) options[:null] = column.null end options[:name] = column.name schema_creation.accept ChangeColumnDefinition.new column, type, options end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 643 def quoted_columns_for_index(column_names, options = {}) option_strings = Hash[column_names.map {|name| [name, '']}] # add index length option_strings = add_index_length(option_strings, column_names, options) # add index sort order option_strings = add_index_sort_order(option_strings, column_names, options) column_names.map {|name| quote_column_name(name) + option_strings[name]} end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 702 def remove_column_sql(table_name, column_name, type = nil, options = {}) "DROP #{quote_column_name(column_name)}" end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 706 def remove_columns_sql(table_name, *column_names) column_names.map {|column_name| remove_column_sql(table_name, column_name) } end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 715 def remove_index_sql(table_name, options = {}) index_name = index_name_for_remove(table_name, options) "DROP INDEX #{index_name}" end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 724 def remove_timestamps_sql(table_name) [remove_column_sql(table_name, :updated_at), remove_column_sql(table_name, :created_at)] end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 687 def rename_column_sql(table_name, column_name, new_column_name) options = { name: new_column_name } if column = columns(table_name).find { |c| c.name == column_name.to_s } options[:default] = column.default options[:null] = column.null options[:auto_increment] = (column.extra == "auto_increment") else raise ActiveRecordError, "No such column: #{table_name}.#{column_name}" end current_type = select_one("SHOW COLUMNS FROM #{quote_table_name(table_name)} LIKE '#{column_name}'", 'SCHEMA')["Type"] schema_creation.accept ChangeColumnDefinition.new column, current_type, options end
MySQL is too stupid to create a temporary table for use subquery, so we have to give it some prompting in the form of a subsubquery. Ugh!
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 621 def subquery_for(key, select) subsubselect = select.clone subsubselect.projections = [key] subselect = Arel::SelectManager.new(select.engine) subselect.project Arel.sql(key.name) subselect.from subsubselect.as('__active_record_temp') end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 655 def translate_exception(exception, message) case error_number(exception) when 1062 RecordNotUnique.new(message, exception) when 1452 InvalidForeignKey.new(message, exception) else super end end
Private Instance Methods
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 734 def column_for(table_name, column_name) unless column = columns(table_name).find { |c| c.name == column_name.to_s } raise "No such column: #{table_name}.#{column_name}" end column end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 741 def configure_connection variables = @config.fetch(:variables, {}).stringify_keys # By default, MySQL 'where id is null' selects the last inserted id. # Turn this off. http://dev.rubyonrails.org/ticket/6778 variables['sql_auto_is_null'] = 0 # Increase timeout so the server doesn't disconnect us. wait_timeout = @config[:wait_timeout] wait_timeout = 2147483 unless wait_timeout.is_a?(Fixnum) variables['wait_timeout'] = self.class.type_cast_config_to_integer(wait_timeout) # Make MySQL reject illegal values rather than truncating or blanking them, see # http://dev.mysql.com/doc/refman/5.0/en/server-sql-mode.html#sqlmode_strict_all_tables # If the user has provided another value for sql_mode, don't replace it. if strict_mode? && !variables.has_key?('sql_mode') variables['sql_mode'] = 'STRICT_ALL_TABLES' end # NAMES does not have an equals sign, see # http://dev.mysql.com/doc/refman/5.0/en/set-statement.html#id944430 # (trailing comma because variable_assignments will always have content) encoding = "NAMES #{@config[:encoding]}, " if @config[:encoding] # Gather up all of the SET variables... variable_assignments = variables.map do |k, v| if v == ':default' || v == :default "@@SESSION.#{k.to_s} = DEFAULT" # Sets the value to the global or compile default elsif !v.nil? "@@SESSION.#{k.to_s} = #{quote(v)}" end # or else nil; compact to clear nils out end.compact.join(', ') # ...and send them all in one query @connection.query "SET #{encoding} #{variable_assignments}" end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 730 def supports_views? version[0] >= 5 end