# File lib/active_record/connection_adapters/mysql_adapter.rb, line 563 def primary_key(table) pk_and_sequence = pk_and_sequence_for(table) pk_and_sequence && pk_and_sequence.first end
The MySQL adapter will work with both Ruby/MySQL, which is a Ruby-based MySQL adapter that comes bundled with Active Record, and with the faster C-based MySQL/Ruby adapter (available both as a gem and from www.tmtm.org/en/mysql/ruby/).
Options:
:host
- Defaults to “localhost”.
:port
- Defaults to 3306.
:socket
- Defaults to “/tmp/mysql.sock”.
:username
- Defaults to “root”
:password
- Defaults to nothing.
:database
- The name of the database. No default, must be
provided.
:encoding
- (Optional) Sets the client encoding by executing
“SET NAMES <encoding>” after connection.
:reconnect
- Defaults to false (See MySQL documentation: dev.mysql.com/doc/refman/5.0/en/auto-reconnect.html).
:sslca
- Necessary to use MySQL with an SSL connection.
:sslkey
- Necessary to use MySQL with an SSL connection.
:sslcert
- Necessary to use MySQL with an SSL connection.
:sslcapath
- Necessary to use MySQL with an SSL connection.
:sslcipher
- Necessary to use MySQL with an SSL connection.
CONNECTION MANAGEMENT ====================================
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 236 def active? if @connection.respond_to?(:stat) @connection.stat else @connection.query 'select 1' end # mysql-ruby doesn't raise an exception when stat fails. if @connection.respond_to?(:errno) @connection.errno.zero? else true end rescue Mysql::Error false end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 470 def add_column(table_name, column_name, type, options = {}) add_column_sql = "ALTER TABLE #{quote_table_name(table_name)} 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) execute(add_column_sql) end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 537 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/mysql_adapter.rb, line 568 def case_sensitive_equality_operator "= BINARY" end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 482 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/mysql_adapter.rb, line 396 def charset show_variable 'character_set_database' end
Returns the database collation strategy.
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 401 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/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/mysql_adapter.rb, line 328 def create_savepoint execute("SAVEPOINT #{current_savepoint_name}") end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 391 def current_database select_value 'SELECT DATABASE() as db' end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 258 def disconnect! @connection.close rescue nil end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 431 def drop_table(table_name, options = {}) super(table_name, options) end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 572 def limited_update_conditions(where_sql, quoted_table_name, quoted_primary_key) where_sql end
Returns just a table’s primary key
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 563 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/mysql_adapter.rb, line 190 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/mysql_adapter.rb, line 217 def quoted_false QUOTED_FALSE end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 213 def quoted_true QUOTED_TRUE end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 253 def reconnect! disconnect! connect end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 336 def release_savepoint execute("RELEASE SAVEPOINT #{current_savepoint_name}") end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 466 def rename_table(table_name, new_name) execute "RENAME TABLE #{quote_table_name(table_name)} TO #{quote_table_name(new_name)}" end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 262 def reset! if @connection.respond_to?(:change_user) # See http://bugs.mysql.com/bug.php?id=33540 -- the workaround way to # reset the connection is to change the user to the same user. @connection.change_user(@config[:username], @config[:password], @config[:database]) configure_connection end end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 332 def rollback_to_savepoint execute("ROLLBACK TO SAVEPOINT #{current_savepoint_name}") end
DATABASE STATEMENTS ======================================
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 273 def select_rows(sql, name = nil) @connection.query_with_result = true result = execute(sql, name) rows = [] result.each { |row| rows << row } result.free @connection.more_results && @connection.next_result # invoking stored procedures with CLIENT_MULTI_RESULTS requires this to tidy up else connection will be dropped rows end
SHOW VARIABLES LIKE ‘name’
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 546 def show_variable(name) variables = select_all("SHOW VARIABLES LIKE '#{name}'") variables.first['Value'] unless variables.empty? end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 417 def table_exists?(name) return true if super 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).include? table end
Maps logical Rails types to MySQL-specific data types.
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 524 def type_to_sql(type, limit = nil, precision = nil, scale = nil) return super unless type.to_s == '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 end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 577 def quoted_columns_for_index(column_names, options = {}) length = options[:length] if options.is_a?(Hash) quoted_column_names = case length when Hash column_names.map {|name| length[name] ? "#{quote_column_name(name)}(#{length[name]})" : quote_column_name(name) } when Fixnum column_names.map {|name| "#{quote_column_name(name)}(#{length})"} else column_names.map {|name| quote_column_name(name) } end end
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 590 def translate_exception(exception, message) return super unless exception.respond_to?(:errno) case exception.errno when 1062 RecordNotUnique.new(message, exception) when 1452 InvalidForeignKey.new(message, exception) else super end 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::MysqlAdapter.emulate_booleans = false
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 132 cattr_accessor :emulate_booleans
# File lib/active_record/connection_adapters/mysql_adapter.rb, line 160 def initialize(connection, logger, connection_options, config) super(connection, logger) @connection_options, @config = connection_options, config @quoted_column_names, @quoted_table_names = {}, {} connect end