# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 585 def primary_key(table) pk_and_sequence = pk_and_sequence_for(table) pk_and_sequence && pk_and_sequence.first end
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 128 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 162 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 }) @visitor = Arel::Visitors::MySQL.new self else @visitor = unprepared_visitor end end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 557 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 308 def begin_db_transaction execute "BEGIN" rescue # Transactions aren't supported end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 314 def begin_isolated_db_transaction(isolation) execute "SET TRANSACTION ISOLATION LEVEL #{transaction_isolation_levels.fetch(isolation)}" begin_db_transaction rescue # Transactions aren't supported end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 594 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 590 def case_sensitive_modifier(node) Arel::Nodes::Bin.new(node) end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 496 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 501 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 400 def charset show_variable 'character_set_database' end
Returns the database collation strategy.
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 405 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 379 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 333 def create_savepoint execute("SAVEPOINT #{current_savepoint_name}") end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 395 def current_database select_value 'SELECT DATABASE() as db' end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 357 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 282 def execute(sql, name = nil) if name == :skip_logging @connection.query(sql) else log(sql, name) { @connection.query(sql) } end rescue ActiveRecord::StatementInvalid => exception if exception.message.split(":").first =~ /Packets out of order/ raise ActiveRecord::StatementInvalid.new("'Packets out of order' error was received from the database. Please update your mysql bindings (gem install mysql) and read http://dev.mysql.com/doc/mysql/en/password-hashing.html for more information. If you're on Windows, use the Instant Rails installer to get the updated mysql bindings.", exception.original_exception) else raise end end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 214 def index_algorithms { default: 'ALGORITHM = DEFAULT', copy: 'ALGORITHM = COPY', inplace: 'ALGORITHM = INPLACE' } end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 602 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 210 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 572 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
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 585 def primary_key(table) pk_and_sequence = pk_and_sequence_for(table) pk_and_sequence && pk_and_sequence.first end
QUOTING ==================================================
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 239 def quote(value, column = nil) if value.kind_of?(String) && column && column.type == :binary && column.class.respond_to?(:string_to_binary) s = column.class.string_to_binary(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 262 def quoted_false QUOTED_FALSE end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 258 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 365 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 341 def release_savepoint execute("RELEASE SAVEPOINT #{current_savepoint_name}") end
Renames a table.
Example:
rename_table('octopuses', 'octopi')
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 491 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 337 def rollback_to_savepoint execute("ROLLBACK TO SAVEPOINT #{current_savepoint_name}") end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 23 def schema_creation SchemaCreation.new self end
SHOW VARIABLES LIKE 'name'
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 566 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 606 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 198 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 179 def supports_migrations? true end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 183 def supports_primary_key? true end
Returns true, since this connection adapter supports savepoints.
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 188 def supports_savepoints? 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 206 def supports_transaction_isolation? version[0] >= 5 end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 419 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
Maps logical Rails types to MySQL-specific data types.
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 526 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 610 def valid_type?(type) !native_database_types[type].nil? end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 663 def add_column_sql(table_name, column_name, type, options = {}) add_column_sql = "ADD #{quote_column_name(column_name)} #{type_to_sql(type, options[:limit], options[:precision], options[:scale])}" add_column_options!(add_column_sql, options) add_column_position!(add_column_sql, options) add_column_sql end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 627 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 712 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 722 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 670 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 change_column_sql = "CHANGE #{quote_column_name(column_name)} #{quote_column_name(column_name)} #{type_to_sql(type, options[:limit], options[:precision], options[:scale])}" add_column_options!(change_column_sql, options) add_column_position!(change_column_sql, options) change_column_sql end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 640 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 704 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 708 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 717 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 726 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 = {} 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"] rename_column_sql = "CHANGE #{quote_column_name(column_name)} #{quote_column_name(new_column_name)} #{current_type}" add_column_options!(rename_column_sql, options) rename_column_sql 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 618 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 652 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
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 736 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 743 def configure_connection variables = @config[:variables] || {} # 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 execute("SET #{encoding} #{variable_assignments}", :skip_logging) end
# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 732 def supports_views? version[0] >= 5 end