lazy-loading

I use JPA (Hibernate) with Spring. When i want to lazy load a Stirng property i use this syntax: @Lob @Basic(fetch = FetchType.LAZY) public String getHtmlSummary() { return htmlSummary; } But when i look at the sql that hibernate creates, it seems this property is not lazy loaded? I also use this class org.hibernate.tool.instrument.javassist.InstrumentTask in ANT script to instrument this property but it seems it does not work. Please help me. Khosro. Lazy Lob loading would require bytecode instrumentation to work properly, so it is not available by default in any JPA implementation I'm aware

I have a legacy database that I am mapping using NHibernate. The objects of concern are an Account and a list of Notification objects. The objects look like: public class Notification { public virtual int Id { get; set; } public virtual DateTime BatchDate { get; set; } /* other properties */ public virtual Account Account { get; set; } } public class Account { public virtual int Id { get; set; } public virtual string AccountNumber { get; set; } /* other properties */ } The mapping files look like: <class name="Account" table="Account" dynamic-update="true"> <id name="Id" column="AccountID">

How yield implements the pattern of lazy loading ? yield implementation doesn't reach the code until it's needed. For example, this code: public IEnumerable<int> GetInts() { yield return 1; yield return 2; yield return 3; } Will actually compile into a nested class which implements IEnumerable<int> and the body of GetInts() will return an instance of that class. Using reflector you can see: public IEnumerable<int> GetInts() { <GetInts>d__6d d__d = new <GetInts>d__6d(-2); d__d.<>4__this = this; return d__d; } Edit - adding more info about GetInts implementation: The way this implementation

I'm using Rails 3.2.0 Let's say I have: class Comment < ActiveRecord::Base has_many :articles end c1 = Comment.last then c1.articles.class # => Array c1.articles.where('id NOT IN (999999)').class # => ActiveRecord::Relation Why is the result of an association not a type of ActiveRecord::Relation ? It clearly is / was at some point : c1.articles.to_orig # undefined method `to_orig' for #<ActiveRecord::Relation:0x007fd820cc80a8> c1.articles.class # => Array Certain evaluations act upon an ActiveRecord::Relation object, but inspecting the class gives a different type. Particularly, this breaks

I have two associated business objects - A and B. the association is (A->B)many-to-one, with B.Id a foreign key in A (so A has A.B_id in the DB). I'm using lazy=true and solved most of my problems, however in A's ToString I want to print also A.B.Id, which I should have without further trips to the DB. but accessing A.B activates the proxy, and since this isn't in the context of an open session, throws an exception. one easy but ugly solution would be to have A.B_id property. but that's part of the stuff we were trying to avoid in the first place. any "organic" way to do this? :) thanks!

How can I tell Activerecord to not load blob columns unless explicitly asked for? There are some pretty large blobs in my legacy DB that must be excluded for 'normal' Objects. I just ran into this using rail 3. Fortunately it wasn't that difficult to solve. I set a default_scope that removed the particular columns I didn't want from the result. For example, in the model I had there was an xml text field that could be quite long that wasn't used in most views. default_scope select((column_names - ['data']).map { |column_name| "`#{table_name}`.`#{column_name}`"}) You'll see from the solution