module ActiveRecord class QueryCache #:nodoc: def initialize(connection) @connection = connection @query_cache = {} end def clear_query_cache @query_cache = {} end def select_all(sql, name = nil) @query_cache[sql] ||= @connection.select_all(sql, name) end def select_one(sql, name = nil) @query_cache[sql] ||= @connection.select_one(sql, name) end def columns(table_name, name = nil) @query_cache["SHOW FIELDS FROM #{table_name}"] ||= @connection.columns(table_name, name) end def insert(sql, name = nil, pk = nil, id_value = nil) clear_query_cache @connection.insert(sql, name, pk, id_value) end def update(sql, name = nil) clear_query_cache @connection.update(sql, name) end def delete(sql, name = nil) clear_query_cache @connection.delete(sql, name) end private def method_missing(method, *arguments) @connection.send(method, *arguments) end end class Base # Set the connection for the class with caching on def self.connection=(spec) raise ConnectionNotEstablished unless spec conn = spec.config[:query_cache] ? QueryCache.new(self.send(spec.adapter_method, spec.config)) : self.send(spec.adapter_method, spec.config) Thread.current['active_connections'] ||= {} Thread.current['active_connections'][self] = conn end end class AbstractAdapter #:nodoc: # Stub method to be able to treat the connection the same whether the query cache has been turned on or not def clear_query_cache end end end