require 'active_record/connection_adapters/abstract_mysql_adapter'
gem 'mysql2', '>= 0.3.18', '< 0.5'
require 'mysql2'
module ActiveRecord
module ConnectionHandling # :nodoc:
# Establishes a connection to the database that's used by all Active Record objects.
def mysql2_connection(config)
config = config.symbolize_keys
config[:username] = 'root' if config[:username].nil?
if Mysql2::Client.const_defined? :FOUND_ROWS
config[:flags] = Mysql2::Client::FOUND_ROWS
end
client = Mysql2::Client.new(config)
options = [config[:host], config[:username], config[:password], config[:database], config[:port], config[:socket], 0]
ConnectionAdapters::Mysql2Adapter.new(client, logger, options, config)
rescue Mysql2::Error => error
if error.message.include?("Unknown database")
raise ActiveRecord::NoDatabaseError.new(error.message, error)
else
raise
end
end
end
module ConnectionAdapters
class Mysql2Adapter < AbstractMysqlAdapter
ADAPTER_NAME = 'Mysql2'.freeze
def initialize(connection, logger, connection_options, config)
super
@prepared_statements = false
configure_connection
end
def supports_json?
version >= '5.7.8'
end
# HELPER METHODS ===========================================
def each_hash(result) # :nodoc:
if block_given?
result.each(:as => :hash, :symbolize_keys => true) do |row|
yield row
end
else
to_enum(:each_hash, result)
end
end
def error_number(exception)
exception.error_number if exception.respond_to?(:error_number)
end
#--
# QUOTING ==================================================
#++
def quote_string(string)
@connection.escape(string)
end
#--
# CONNECTION MANAGEMENT ====================================
#++
def active?
return false unless @connection
@connection.ping
end
def reconnect!
super
disconnect!
connect
end
alias :reset! :reconnect!
# Disconnects from the database if already connected.
# Otherwise, this method does nothing.
def disconnect!
super
unless @connection.nil?
@connection.close
@connection = nil
end
end
#--
# DATABASE STATEMENTS ======================================
#++
# FIXME: re-enable the following once a "better" query_cache solution is in core
#
# The overrides below perform much better than the originals in AbstractAdapter
# because we're able to take advantage of mysql2's lazy-loading capabilities
#
# # Returns a record hash with the column names as keys and column values
# # as values.
# def select_one(sql, name = nil)
# result = execute(sql, name)
# result.each(as: :hash) do |r|
# return r
# end
# end
#
# # Returns a single value from a record
# def select_value(sql, name = nil)
# result = execute(sql, name)
# if first = result.first
# first.first
# end
# end
#
# # Returns an array of the values of the first column in a select:
# # select_values("SELECT id FROM companies LIMIT 3") => [1,2,3]
# def select_values(sql, name = nil)
# execute(sql, name).map { |row| row.first }
# end
# Returns an array of arrays containing the field values.
# Order is the same as that returned by +columns+.
def select_rows(sql, name = nil, binds = [])
execute(sql, name).to_a
end
# Executes the SQL statement in the context of this connection.
def execute(sql, name = nil)
if @connection
# make sure we carry over any changes to ActiveRecord::Base.default_timezone that have been
# made since we established the connection
@connection.query_options[:database_timezone] = ActiveRecord::Base.default_timezone
end
super
end
def exec_query(sql, name = 'SQL', binds = [])
result = execute(sql, name)
ActiveRecord::Result.new(result.fields, result.to_a)
end
alias exec_without_stmt exec_query
def insert_sql(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil)
super
id_value || @connection.last_id
end
alias :create :insert_sql
def exec_insert(sql, name, binds, pk = nil, sequence_name = nil)
execute to_sql(sql, binds), name
end
def exec_delete(sql, name, binds)
execute to_sql(sql, binds), name
@connection.affected_rows
end
alias :exec_update :exec_delete
def last_inserted_id(result)
@connection.last_id
end
private
def connect
@connection = Mysql2::Client.new(@config)
configure_connection
end
def configure_connection
@connection.query_options.merge!(:as => :array)
super
end
def full_version
@full_version ||= @connection.server_info[:version]
end
def set_field_encoding field_name
field_name
end
end
end
end