datamapper

问题 This question comes along NoUniqueBeanDefinitionException when multiple datasouces in Spring Boot and Mybatis project. I try to configure two dataSources in Spring Boot and MyBatis project, but exception occurs: org.apache.ibatis.binding.BindingException: Invalid bound statement (not found): com.bookSystem.mapper.UserDao.findByDomain at org.apache.ibatis.binding.MapperMethod$SqlCommand.(MapperMethod.java:227) ~[mybatis-3.4.6.jar:3.4.6] at org.apache.ibatis.binding.MapperMethod.(MapperMethod

问题 Using Data Mapper Pattern: an object/entity is unaware of data mapper and storage (e.g. RDBMS). storage is unaware of data mapper and object/entity. data mapper is of course aware and bridge the object/entity and storage. How do I validate a unique field in an object/entity (e.g. $user->name ) without it be aware of data mapper and storage (i.e. $user cannot simply call $userDataMapper->count('name='.$this->name) )? class User { private $name; // unique public function validate(): bool { //

问题 I have a project that uses CoreData on iOS and we have gone through numerous model updates with the lightweight migration technique and the NSInferMappingModelAutomaticallyOption set to YES. This works perfectly fine, but for the current transition we need to specify some more information and thus create a mapping model. I created the mapper by going to File->New and create a new data model mapper that maps the old version of my model to the new version. The mapper is in the Resources folder

问题 I have a Ruby program that uses DataMapper as an ORM to talk to an in-memory SQLite DB. This has been working fine, however I just recently added a new DM class, and corresponding table. To my surprise, things now blow up during an auto_migrate! here is the SQL generated by DataMapper: ~ (0.000390) PRAGMA table_info("sensationd_channels") ~ (0.000010) PRAGMA table_info("sensationd_commands") ~ (0.000009) PRAGMA table_info("sensationd_configurations") ~ (0.000052) PRAGMA table_info("sensationd

问题 Hopefully i am asking this on the right stack exchange forum. If not please do let me know and I will ask somewhere else. I have also asked on Code Review, but the community seems a lot less active. As I have self learned PHP and all programming in general, I have only recently found out about 'Data Mappers' which allows data to be passed into classes without said classes knowing where the data comes from. I have read some of the positives of using mappers and why they make it 'easier' to

问题 Some background first: I have a few rather simple data structures which are persisted as json files on disk. These json files are shared between applications of different languages and different environments (like web frontend and data manipulation tools). For each of the files I want to create a Python "POPO" (Plain Old Python Object), and a corresponding data mapper class for each item should implement some simple CRUD like behavior (e.g. save will serialize the class and store as json file

问题 It's very simple, I want to handle a normal [show] request with a call to DataMapper like I did in Merb. With ActiveRecord I could have done this: class PostsController def show @post = Post.get(params[:id]) @comments = @post.comments unless @post.nil? end end and it handles the 404 by catching the resource's exceptions. DataMapper instead doesn't do this automatically so right now I'm solving it with this solution: [moved in the answers] It is possible to tell the controller to halt inside

问题 I'm reading the architectural patterns chapter of POEAA, and Fowler says that "As the domain logic gets more complicated and you begin moving toward a rich Domain Model (116), the simple approach of an Active Record (160) starts to break down. The one-to-one match of domain classes to tables starts to fail as you factor domain logic into smaller classes. Relational databases don't handle inheritance, so it becomes difficult to use strategies [Gang of Four] and other neat OO patterns. As the

问题 We are using Datamapper in a Sinatra application and would like to use case insensitive like that works on both Sqlite (locally in development) and Postgresql (on Heroku in production). We have statements like TreeItem.all(:name.like =>"%#{term}%",:unique => true,:limit => 20) If term is "BERL" we get the suggestion "BERLIN" from both the Sqlite and Postgresql backends. However if term is "Berl" we only get that result from Sqlite and not Postgresql. I guess this has to do with the fact that

问题 I'm trying to make a simple room management service. The rooms have these properties: class Room include DataMapper::Resource validates_is_unique :number property :id, Serial property :number, Integer property :guest, String property :status, Enum[ :free, :occupied ], :default => :free end Then I create a new room like this post '/new' do content_type :json @room = Room.new :guest => params[:guest], :number => params[:number], :status => params[:status] if @room.save { :number => @room.number