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• Delete record in Linq to Sql

  - by Anders Svensson

  I have Linq2Sql classes User, Page, and UserPage (from a junction table), i.e. a many-to-many relationship. I'm using a gridview to show all Users, with a dropdownlist in each row to show the Pages visited by each user. Now I want to be able to delete records through the gridview, so I have added a delete button in the gridview by setting "Enable deleting" on it. Then I tried to use the RowDeleting event to specify how to delete the records since it doesn't work by default. And because its a relationship I know I need to delete the related records in the junction table before deleting the user record itself, so I added this in the RowDeleting event: protected void GridView2_RowDeleting(object sender, GridViewDeleteEventArgs e) { int id = (int)((DataKey)GridView2.DataKeys[e.RowIndex]).Value; UserPageDBDataContext context = new UserPageDBDataContext(); var userPages = from userPage in context.UserPages where userPage.User.UserID == id select userPage; foreach (var userPage in userPages) context.UserPages.DeleteOnSubmit(userPage); context.SubmitChanges(); var user = context.Users.Single(u => u.UserID == id); context.Users.DeleteOnSubmit(user); context.SubmitChanges(); } This actually seems to delete records, because the record with the id in question does indeed disappear, but strangely, a new record seems to be added at the end...! So, say I have 3 records in the gridview: 1 Jack stackoverflow.com 2 Betty stackoverflow.com/questions 3 Joe stackoverflow.com/whatever Now, if I try to delete user 1 (Jack), record number 1 will indeed disappear in the gridview, but the same record will appear at the end with a new id: 2 Jack stackoverflow.com 3 Betty stackoverflow.com/questions 4 Joe stackoverflow.com/whatever I have tried searching on how to delete records using Linq, and I believe I'm doing exacly as the examples I have read (e.g. the second example here: http://msdn.microsoft.com/en-us/library/Bb386925%28v=VS.100%29.aspx). I have read that you can also set cascade delete on the relationship in the database, but I wanted to do it this way in code, as your supposed to be able to. So what am I doing wrong?

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• USE case to Class Diagram - How do I?

  - by 01010011

  Hi, I would like your guidance on how to create classes and their relationships (generalization, association, aggregation and composition) accurately from my USE case diagram (please see below). I am trying to create this class diagram so I can use it to create a simple online PHP application that allows the user to register an account, login and logout, and store, search and retrieve data from a MySQL database. Are my classes correct? Or should I create more classes? And if so, what classes are missing? What relationships should I use when connecting the register, login, logout, search_database and add_to_database to the users? I'm new to design patterns and UML class diagrams but from my understanding, the association relationship relates one object with another object; the aggregation relationship is a special kind of association that allows "a part" to belong to more than one "whole" (e.g. a credit card and its PIN - the PIN class can also be used in a debit card class); and a composition relationship is a special form of aggregation that allows each part to belong to only one whole at a time. I feel like I have left out some classes or something because I just can't seem to find the relationships from my understanding of relationships. Any assistance will be really appreciated. Thanks in advance. USE CASE DIAGRAM CLASS DIAGRAM

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• Building a many-to-many db schema using only an unpredictable number of foreign keys

  - by user1449855

  Good afternoon (at least around here), I have a many-to-many relationship schema that I'm having trouble building. The main problem is that I'm only working with primary and foreign keys (no varchars or enums to simplify things) and the number of many-to-many relationships is not predictable and can increase at any time. I looked around at various questions and couldn't find something that directly addressed this issue. I split the problem in half, so I now have two one-to-many schemas. One is solved but the other is giving me fits. Let's assume table FOO is a standard, boring table that has a simple primary key. It's the one in the one-to-many relationship. Table BAR can relate to multiple keys of FOO. The number of related keys is not known beforehand. An example: From a query FOO returns ids 3, 4, 5. BAR needs a unique key that relates to 3, 4, 5 (though there could be any number of ids returned) The usual join table does not work: Table FOO_BAR primary_key | foo_id | bar_id | Since FOO returns 3 unique keys and here bar_id has a one-to-one relationship with foo_id. Having two join tables does not seem to work either, as it still can't map foo_ids 3, 4, 5 to a single bar_id. Table FOO_TO_BAR primary_key | foo_id | bar_to_foo_id | Table BAR_TO_FOO primary_key | foo_to_bar_id | bar_id | What am I doing wrong? Am I making things more complicated than they are? How should I approach the problem? Thanks a lot for the help.

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• Modeling multiple polymorphic relationships using Hibernate

  - by f-potter

  Ruby on Rails has polymorphic relations which are really useful for implementing functionality such as commenting, tagging and rating to name a few. We can have a comment, tag or rating class which has a many to one polymorphic relationship with a commentable, taggable and rateable object. Also, a given domain object can choose to implement any combination of such relations. So, it can for example be commentable, taggable and rateable at the same time. I couldn't think up of a straightforward way to duplicate this functionality in Hibernate. Ideally, there would be a Comment class which will have a many to one relationship with a Commentable class and a Commentable class will conversely have a one to many relationship with Comments. It will be ideal if the concrete domain classes can inherit from a number of such classes, say Commentable and Taggable. Things seem a little complicated as a Java class can only extend one other class and some code might end up being duplicated across a number of classes. I wanted to know what are the best practices for modeling such relationships neatly and concisely using Hibernate?

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• Linq is returning too many results when joined

  - by KallDrexx

  In my schema I have two database tables. relationships and relationship_memberships. I am attempting to retrieve all the entries from the relationship table that have a specific member in it, thus having to join it with the relationship_memberships table. I have the following method in my business object: public IList<DBMappings.relationships> GetRelationshipsByObjectId(int objId) { var results = from r in _context.Repository<DBMappings.relationships>() join m in _context.Repository<DBMappings.relationship_memberships>() on r.rel_id equals m.rel_id where m.obj_id == objId select r; return results.ToList<DBMappings.relationships>(); } _Context is my generic repository using code based on the code outlined here. The problem is I have 3 records in the relationships table, and 3 records in the memberships table, each membership tied to a different relationship. 2 membership records have an obj_id value of 2 and the other is 3. I am trying to retrieve a list of all relationships related to object #2. When this linq runs, _context.Repository<DBMappings.relationships>() returns the correct 3 records and _context.Repository<DBMappings.relationship_memberships>() returns 3 records. However, when the results.ToList() executes, the resulting list has 2 issues: 1) The resulting list contains 6 records, all of type DBMappings.relationships(). Upon further inspection there are 2 for each real relationship record, both are an exact copy of each other. 2) All relationships are returned, even if m.obj_id == 3, even though objId variable is correctly passed in as 2. Can anyone see what's going on because I've spent 2 days looking at this code and I am unable to understand what is wrong. I have joins in other linq queries that seem to be working great, and my unit tests show that they are still working, so I must be doing something wrong with this. It seems like I need an extra pair of eyes on this one :)

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• How to bundle extension methods requiring configuration in a library

  - by Greg

  Hi, I would like to develop a library that I can re-use to add various methods involved in navigating/searching through a graph (nodes/relationships, or if you like vertexs/edges). The generic requirements would be: There are existing classes in the main project that already implement the equivalent of the graph class (which contains the lists of nodes / relationships), node class and relationship class (which links nodes together) - the main project likely already has persistence mechanisms for the info (e.g. these classes might be built using Entity Framework for persistance) Methods would need to be added to each of these 3 classes: (a) graph class - methods like "search all nodes", (b) node class - methods such as "find all children to depth i", c) relationship class - methods like "return relationship type", "get parent node", "get child node". I assume there would be a need to inform the library with the extending methods the class names for the graph/node/relationships table (as different project might use different names). To some extent it would need to be like how a generics collection works (where you pass the classes to the collection so it knows what they are). Need to be a way to inform the library of which node property to use for equality checks perhaps (e.g. if it were a graph of webpages the equality field to use might be the URI path) I'm assuming that using abstract base classes wouldn't really work as this would tie usage down to have to use the same persistence approach, and same class names etc. Whereas really I want to be able to, for a project that has "graph-like" characteristics, the ability to add graph searching/walking methods to it.

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• Using HABTM relationships in cakephp plugins with unique set to false

  - by Dean

  I am working on a plugin for our CakePHP CMS that will handle blogs. When getting to the tags I needed to set the HABTM relationship to unique = false to be able add tags to a post without having to reset them all. The BlogPost model looks like this class BlogPost extends AppModel { var $name = 'BlogPost'; var $actsAs = array('Core.WhoDidIt', 'Containable'); var $hasMany = array('Blog.BlogPostComment'); var $hasAndBelongsToMany = array('Blog.BlogTag' => array('unique' => false), 'Blog.BlogCategory'); } The BlogTag model looks like this class BlogTag extends AppModel { var $name = 'BlogTag'; var $actsAs = array('Containable'); var $hasAndBelongsToMany = array('Blog.BlogPost'); } The SQL error I am getting when I have the unique = true setting in the HABTM relationship between the BlogPost and BlogTag is Query: SELECT `Blog`.`BlogTag`.`id`, `Blog`.`BlogTag`.`name`, `Blog`.`BlogTag`.`slug`, `Blog`.`BlogTag`.`created_by`, `Blog`.`BlogTag`.`modified_by`, `Blog`.`BlogTag`.`created`, `Blog`.`BlogTag`.`modified`, `BlogPostsBlogTag`.`blog_post_id`, `BlogPostsBlogTag`.`blog_tag_id` FROM `blog_tags` AS `Blog`.`BlogTag` JOIN `blog_posts_blog_tags` AS `BlogPostsBlogTag` ON (`BlogPostsBlogTag`.`blog_post_id` = 4 AND `BlogPostsBlogTag`.`blog_tag_id` = `Blog`.`BlogTag`.`id`) As you can see it is trying to set the blog_tags table to 'Blog'.'BlogTag. which isn't a valid MySQL name. When I remove the unique = true from the relationship it all works find and I can save one tag but when adding another it just erases the first one and puts the new one in its place. Does anyone have any ideas? is it a bug or am I just missing something? Cheers, Dean

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• Using ASP.NET SQL Membership Provider, how do I store my own per-user data?

  - by Gary McGill

  I'm using the ASP.NET SQL Membership Provider. So, there's an aspnet_Users table that has details of each of my users. (Actually, the aspnet_Membership table seems to contain most of the actual data). I now want to store some per-user information in my database, so I thought I'd just create a new table with a UserId (GUID) column and an FK relationship to aspnet_Users. However, I then discovered that I can't easily get access to the UserId since it's not exposed via the membership API. (I know I can access it via the ProviderUserKey, but it seems like the API is abstracting away the internal UserID in favor of the UserName, and I don't want to go too far against the grain). So, I thought I should instead put a LoweredUserName column in my table, and create an FK relationship to aspnet_Users using that. Bzzzt. Wrong again, because while there is a unique index in aspnet_Users that includes the LoweredUserName, it also includes the ApplicationId - so in order to create my FK relationship, I'd need to have an ApplicationId column in my table too. At first I thought: fine, I'm only dealing with a single application, so I'll just add such a column and give it a default value. Then I realised that the ApplicationId is a GUID, so it'd be a pain to do this. Not hard exactly, but until I roll out my DB I can't predict what the GUID is going to be. I feel like I'm missing something, or going about things the wrong way. What am I supposed to do?

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• table subtraction challenge

  - by Valentin

  I have a challenge that I haven’t overcome in the last two days using Stored Procedures and SQL 2008. I took several approaches but must fell short. One appraoch very interesting was using a table substraction. It’s really all about table subtraction. I was wondering if you could help me crack this one. Here is the challenge: Two tables 1Testdb y 2Testdb. My first step was to select ID relationships ([2Testdb].Acc_id) on table 2Testdb for one given individual ([2Testdb].Bus_id). Then query table 1Testdb for records not mathcing my original selection from 2Testdb. But other approaches are welcome. Data and Structures: USE [Challengedb] GO SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TABLE [dbo].[1Testdb]( [Acc_id] [uniqueidentifier] NULL [Name] [Varchar(10)] NULL ) ON [PRIMARY] GO CREATE TABLE [dbo].[2Testdb]( [Acc_id] [uniqueidentifier] NULL, [Bus_id] [uniqueidentifier] NULL ) ON [PRIMARY] GO Records on 1Testdb: 34455F60-9474-4521-804E-66DB39A579F3, John C23523F6-2309-4F58-BB3F-EF7486C7AF8B, Pete DC711615-3BE4-4B31-9EF2-B1314185CA62, Dave E3AAB073-2398-476D-828B-92829F686A4C, Adam Records on 2Testdb: (Relationship table, ex. Friend relationships) Record #1: DC711615-3BE4-4B31-9EF2-B1314185CA62, 34455F60-9474-4521-804E-66DB39A579F3 Record #2: E3AAB073-2398-476D-828B-92829F686A4C, 34455F60-9474-4521-804E-66DB39A579F3 Record # 3: DC711615-3BE4-4B31-9EF2-B1314185CA62, E3AAB073-2398-476D-828B-92829F686A4C Record # 4: E3AAB073-2398-476D-828B-92829F686A4C, DC711615-3BE4-4B31-9EF2-B1314185CA62 Challenge: Select from table 1Testdb only those records distinct that may not have a relationship with John [34455F60-9474-4521-804E-66DB39A579F3] on table 2Testdb. Expected result should be (Who does John doesn’t have relationship with?): C23523F6-2309-4F58-BB3F-EF7486C7AF8B, Pete Thank you, Valentin

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• How to exclude rows where matching join is in an SQL tree

  - by Greg K

  Sorry for the poor title, I couldn't think how to concisely describe this problem. I have a set of items that should have a 1-to-1 relationship with an attribute. I have a query to return those rows where the data is wrong and this relationship has been broken (1-to-many). I'm gathering these rows to fix them and restore this 1-to-1 relationship. This is a theoretical simplification of my actual problem but I'll post example table schema here as it was requested. item table: +------------+------------+-----------+ | item_id | name | attr_id | +------------+------------+-----------+ | 1 | BMW 320d | 20 | | 1 | BMW 320d | 21 | | 2 | BMW 335i | 23 | | 2 | BMW 335i | 34 | +------------+------------+-----------+ attribute table: +---------+-----------------+------------+ | attr_id | value | parent_id | +---------+-----------------+------------+ | 20 | SE | 21 | | 21 | M Sport | 0 | | 23 | AC | 24 | | 24 | Climate control | 0 | .... | 34 | Leather seats | 0 | +---------+-----------------+------------+ A simple query to return items with more than one attribute. SELECT item_id, COUNT(DISTINCT(attr_id)) AS attributes FROM item GROUP BY item_id HAVING attributes > 1 This gets me a result set like so: +-----------+------------+ | item_id | attributes | +-----------+------------+ | 1 | 2 | | 2 | 2 | | 3 | 2 | -- etc. -- However, there's an exception. The attribute table can hold a tree structure, via parent links in the table. For certain rows, parent_id can hold the ID of another attribute. There's only one level to this tree. Example: +---------+-----------------+------------+ | attr_id | value | parent_id | +---------+-----------------+------------+ | 20 | SE | 21 | | 21 | M Sport | 0 | .... I do not want to retrieve items in my original query where, for a pair of associated attributes, they related like attributes 20 & 21. I do want to retrieve items where: the attributes have no parent for two or more attributes they are not related (e.g. attributes 23 & 34) Example result desired, just the item ID: +------------+ | item_id | +------------+ | 2 | +------------+ How can I join against attributes from items and exclude these rows? Do I use a temporary table or can I achieve this from a single query? Thanks.

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• How to use Many to Many in Rails?

  - by Newbie

  Hello! In my project, I have users and quests. One User can join multiple quests and one quest can have multiple users. So I created a table called questing, containing the user_id and the quest_id. In my user.rb I did following: require 'digest/sha1' class User < ActiveRecord::Base has_many :questings has_many :quests ,:through =>:questings ... My Quest.rb: class Quest < ActiveRecord::Base has_many :questings has_many :users ,:through =>:questings ... My Questing.rb: class Questing < ActiveRecord::Base belongs_to :quest belongs_to :user end Now I want to create a link or button on my /quests/show.html.erb, calling an action in my controller, which will create the relationship between user and quest. So, in my quest_controller I did: def join_quest @quest = Quest.find(params[:id]) puts '************************' puts 'join quest:' + @quest.id puts '************************' respond_to do |format| format.html { redirect_to(@quest) } format.xml { head :ok } end end and in my show.html.erb I did: <%= link_to 'join this quest!!!', :action => :join_quest %> Now, clicking on this link will cause an error like: Couldn't find Quest with ID=join_quest and the url points to */quests/join_quest* instead of */quests/1/join_quest* Now my questions: Is my quests_controller the right place for my join_quest action, or should I move it to my users_controller? Why do I get this error? How to solve it? What do I have to write in my join_quest action for saving the relationship? On my /users/show.html.erb I want to output all quests the user joined. How to do this? I have to get all this quests from my relationship table, right? How? I hope you can help me! THX!

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• HABTM selection seemingly ignores joinTable

  - by TheCapn

  I'm attempting to do a HABTM relationship between a Users table and Groups table. The problem is, that I when I issue this call: $this->User->Group->find('list'); The query that is issued is: SELECT [Group].[id] AS [Group__id], [Group].[name] AS [Group__name] FROM [groups] AS [Group] WHERE 1 = 1 I can only assume at this point that I have defined my relationship wrong as I would expect behavior to use the groups_users table that is defined on the database as per convention. My relationships: class User extends AppModel { var $name = 'User'; //...snip... var $hasAndBelongsToMany = array( 'Group' => array( 'className' => 'Group', 'foreignKey' => 'user_id', 'associationForeignKey' => 'group_id', 'joinTable' => 'groups_users', 'unique' => true, ) ); //...snip... } class Group extends AppModel { var $name = 'Group'; var $hasAndBelongsToMany = array ( 'User' => array( 'className' => 'User', 'foreignKey' => 'group_id', 'associationForeignKey' => 'user_id', 'joinTable' => 'groups_users', 'unique' => true, )); } Is my understanding of HABTM wrong? How would I implement this Many to Many relationship where I can use CakePHP to query the groups_users table such that a list of groups the currently authenticated user is associated with is returned?

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• Design Advice Needed For Synonyms Database

  - by James J

  I'm planning to put together a database that can be used to query synonyms of words. The database will end up huge, so the idea is to keep things running fast. I've been thinking about how to do this, but my database design skills are not up to scratch these days. My initial idea was to have each word stored in one table, and then another table with a 1 to many relationship where each word can be linked to another word and that table can be queried. The application I'm developing allows users to highlight a word, and then type in, or select some synonyms from the database for that word. The application learns from the user input so if someone highlights "car" and types in "motor" the database would be updated to link the relationship if it don't exist already. What I don't want to happen is for a user to type in the word "shop" and link it to the word car. So I'm thinking I will need to add some sort of weight to each relationship. Eventually the synonyms the users enter will be used so they can auto select common synonyms used with a certain word. The lower weight words will not be displayed so shop could never be a synonym of car unless it had a very high weight, and chances are nobody is going to do that. Does the above sound right? Can you offer any suggestions or improvements?

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• Silverlight 4 WCF RIA Services and MVVM is not as simple

  - by Thomas Jaskula

  [Disclaimer: I'm ASP.NET MVC Developer] Hi, I'm looking for some best practices with implementing MVVM pattern with WCF RIA in Silverlight 4. I'm not looking to use MEF of IoC for locating my ViewModels. What I would like to know is how to apply MVVM pattern with Silverlight 4 and WCF RIA. I don't want to use other stuff like Prism or MVVM Light toolkit. I found many examples on Internet showing how it is wonderful to drag and drop a datasource on the view and the job is done (it reminds me about my first VB6 developments). I tried to implement MVVM with WCF RIA and it's not strightforward at all. If I understand, the MVVM should contain all the logic in order to unit test it in isolation but when it comes to combine it with WCF RIA it's another story. I have the following questions. Can I use a generated metadata as model ? It would be easier to use it that if I write all from the scratch. As I saw the only way I could get data is through DomainContext or through direct binding in the view (local ressource). I don't want the direct binding in the view, not testable at all. On the other hand I can't use DomainContext, it doesn't expose any single entity !!! All I have is the EntitySet that I can bind to datagrid. How do I bind a single Entity to the DataForm from the ViewModel ? How do I udpate the model to the database ? How do I navigate from one Entity to a collection of it's itemps. For example if I have a Company Entity I would like to show a DataFrom to update a entite informations and a datagrid to show companies adresses. When saving a form would like to save information to Company and for example an information avout which adress was selected as active. Please help me understand how to do it well. Or maybe I should drop the WCF RIA and to do it with WCF from scratch ? What do you think ?

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• I am getting an error with a oneToMany association when using annotations with gilead for hibernate

  - by user286630

  Hello Guys I'm using Gilead to persist my entities in my GWT project, im using hibernate annotations aswell. my problem is on my onetomany association.this is my User class that holds a reference to a list of FileLocations @Entity @Table(name = "yf_user_table") public class YFUser implements Serializable { @Id @GeneratedValue(strategy = GenerationType.AUTO) @Column(name = "user_id",nullable = false) private int userId; @Column(name = "username") private String username; @Column(name = "password") private String password; @Column(name = "email") private String email; @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY) @JoinColumn(name="USER_ID") private List fileLocations = new ArrayList(); This is my file location class @Entity @Table(name = "fileLocationTable") public class FileLocation implements Serializable { @Id @GeneratedValue(strategy = GenerationType.AUTO) @Column(name = "locationId", updatable = false, nullable = false) private int ieId; @Column (name = "location") private String location; @ManyToOne(fetch=FetchType.LAZY) @JoinColumn(name="USER_ID", nullable=false) private YFUser uploadedUser; When i persist this data in a normal desktop application, it works fine , creates the tables and i can add and store data to it. but when i try to persist the data in my gwt application i get errors i will show them lower. this is my ServiceImpl class that extends PersistentRemoteService. public class TestServiceImpl extends PersistentRemoteService implements TestService { public static final String SESSION_USER = "UserWithinSession"; public TestServiceImpl(){ HibernateUtil util = new HibernateUtil(); util.setSessionFactory(com.example.server.HibernateUtil .getSessionFactory()); PersistentBeanManager pbm = new PersistentBeanManager(); pbm.setPersistenceUtil(util); pbm.setProxyStore(new StatelessProxyStore()); setBeanManager(pbm); } @Override public String registerUser(String username, String password, String email) { Session session = com.example.server.HibernateUtil.getSessionFactory().getCurrentSession(); session.beginTransaction(); YFUser newUser = new YFUser(); newUser.setUsername(username);newUser.setPassword(password);newUser.setEmail(email); session.save(newUser); session.getTransaction().commit(); return "Thank you For registering "+ username; } this is the error that im am getting. the error goes away when i remove my onetoManyRelationship and builds my session factory when i put it in , it on the line of buildsessionfactory in hibernate Util that it throws this exception. my hibernate util class is ok also. this is the error java.lang.NoSuchMethodError: javax.persistence.OneToMany.orphanRemoval()Z Mar 24, 2010 10:03:22 PM org.hibernate.cfg.annotations.Version <clinit> INFO: Hibernate Annotations 3.5.0-Beta-4 Mar 24, 2010 10:03:22 PM org.hibernate.cfg.Environment <clinit> INFO: Hibernate 3.5.0-Beta-4 Mar 24, 2010 10:03:22 PM org.hibernate.cfg.Environment <clinit> INFO: hibernate.properties not found Mar 24, 2010 10:03:22 PM org.hibernate.cfg.Environment buildBytecodeProvider INFO: Bytecode provider name : javassist Mar 24, 2010 10:03:22 PM org.hibernate.cfg.Environment <clinit> INFO: using JDK 1.4 java.sql.Timestamp handling Mar 24, 2010 10:03:22 PM org.hibernate.annotations.common.Version <clinit> INFO: Hibernate Commons Annotations 3.2.0-SNAPSHOT Mar 24, 2010 10:03:22 PM org.hibernate.cfg.Configuration configure INFO: configuring from resource: /hibernate.cfg.xml Mar 24, 2010 10:03:22 PM org.hibernate.cfg.Configuration getConfigurationInputStream INFO: Configuration resource: /hibernate.cfg.xml Mar 24, 2010 10:03:22 PM org.hibernate.cfg.Configuration doConfigure INFO: Configured SessionFactory: null Mar 24, 2010 10:03:22 PM org.hibernate.cfg.search.HibernateSearchEventListenerRegister enableHibernateSearch INFO: Unable to find org.hibernate.search.event.FullTextIndexEventListener on the classpath. Hibernate Search is not enabled. Mar 24, 2010 10:03:22 PM org.hibernate.cfg.AnnotationBinder bindClass INFO: Binding entity from annotated class: com.example.client.Entity1 Mar 24, 2010 10:03:22 PM org.hibernate.cfg.annotations.EntityBinder bindTable INFO: Bind entity com.example.client.Entity1 on table entityTable1 Mar 24, 2010 10:03:22 PM org.hibernate.cfg.AnnotationBinder bindClass INFO: Binding entity from annotated class: com.example.client.YFUser Mar 24, 2010 10:03:22 PM org.hibernate.cfg.annotations.EntityBinder bindTable INFO: Bind entity com.example.client.YFUser on table yf_user_table Initial SessionFactory creation failed.java.lang.NoSuchMethodError: javax.persistence.OneToMany.orphanRemoval()Z [WARN] Nested in javax.servlet.ServletException: init: java.lang.ExceptionInInitializerError at com.example.server.HibernateUtil.<clinit>(HibernateUtil.java:38) at com.example.server.TestServiceImpl.<init>(TestServiceImpl.java:29) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39 ) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at java.lang.Class.newInstance0(Class.java:355) at java.lang.Class.newInstance(Class.java:308) at org.mortbay.jetty.servlet.Holder.newInstance(Holder.java:153) at org.mortbay.jetty.servlet.ServletHolder.getServlet(ServletHolder.java:339) at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:463) at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:362) at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216) at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:181) at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:729) at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:405) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) at org.mortbay.jetty.handler.RequestLogHandler.handle(RequestLogHandler.java:49) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) at org.mortbay.jetty.Server.handle(Server.java:324) at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:505) at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:843) at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:647) at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:211) at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:380) at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:396) at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:488) Caused by: java.lang.NoSuchMethodError: javax.persistence.OneToMany.orphanRemoval()Z at org.hibernate.cfg.AnnotationBinder.processElementAnnotations(AnnotationBinder.java:1642) at org.hibernate.cfg.AnnotationBinder.bindClass(AnnotationBinder.java:772) at org.hibernate.cfg.AnnotationConfiguration.processArtifactsOfType(AnnotationConfiguration.java:629) at org.hibernate.cfg.AnnotationConfiguration.secondPassCompile(AnnotationConfiguration.java:350) at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1373) at org.hibernate.cfg.AnnotationConfiguration.buildSessionFactory(AnnotationConfiguration.java:973) at com.example.server.HibernateUtil.<clinit>(HibernateUtil.java:33) ... 26 more [WARN] Nested in java.lang.ExceptionInInitializerError: java.lang.NoSuchMethodError: javax.persistence.OneToMany.orphanRemoval()Z at org.hibernate.cfg.AnnotationBinder.processElementAnnotations(AnnotationBinder.java:1642) at org.hibernate.cfg.AnnotationBinder.bindClass(AnnotationBinder.java:772) at org.hibernate.cfg.AnnotationConfiguration.processArtifactsOfType(AnnotationConfiguration.java:629) at org.hibernate.cfg.AnnotationConfiguration.secondPassCompile(AnnotationConfiguration.java:350) at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1373) at org.hibernate.cfg.AnnotationConfiguration.buildSessionFactory(AnnotationConfiguration.java:973) at com.example.server.HibernateUtil.<clinit>(HibernateUtil.java:33) at com.example.server.TestServiceImpl.<init>(TestServiceImpl.java:29) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at java.lang.Class.newInstance0(Class.java:355) at java.lang.Class.newInstance(Class.java:308) at org.mortbay.jetty.servlet.Holder.newInstance(Holder.java:153) at org.mortbay.jetty.servlet.ServletHolder.getServlet(ServletHolder.java:339) at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:463) at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:362) at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216) at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:181) at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:729) at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:405) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) at org.mortbay.jetty.handler.RequestLogHandler.handle(RequestLogHandler.java:49) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) at org.mortbay.jetty.Server.handle(Server.java:324) at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:505) at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:843) at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:647) at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:211) at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:380) at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:396) at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:488)

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• LLBLGen Pro v2.6 designer issue

  - by Luis

  How do you delete more than one entity at the same time in the designer Entities list. it seems that the designer interface only allows the selection of 1 entity at a time.... This is frustrating, is this possible? Or even deleting all entities? Thanks Regards Luis

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• PlayFramework with Scala and Morphia

  - by AKRamkumar

  I keep getting this exception: Oops: CannotCompileException An unexpected error occured caused by exception CannotCompileException: [source error] ds() not found in models.dc What is wrong with my code? Here is models.ds package models import com.google.code.morphia.annotations._ @Embedded class ds{ @Indexed var xs : Double=0 @Indexed var xc : Double=0 @Indexed var ys : Double=0 @Indexed var yc : Double=0 @Indexed var zs : Double=0 @Indexed var zc : Double=0 } Here is models.dc package models import com.google.code.morphia.annotations.{Embedded, Entity, Indexed} @Entity class dc{ @Indexed var name : String = null @Embedded var summary : ds = new ds() }

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• Add objects to association in OnPreInsert, OnPreUpdate

  - by Dmitriy Nagirnyak

  Hi, I have an event listener (for Audit Logs) which needs to append audit log entries to the association of the object: public Company : IAuditable { // Other stuff removed for bravety IAuditLog IAuditable.CreateEntry() { var entry = new CompanyAudit(); this.auditLogs.Add(entry); return entry; } public virtual IEnumerable<CompanyAudit> AuditLogs { get { return this.auditLogs } } } The AuditLogs collection is mapped with cascading: public class CompanyMap : ClassMap<Company> { public CompanyMap() { // Id and others removed fro bravety HasMany(x => x.AuditLogs).AsSet() .LazyLoad() .Access.ReadOnlyPropertyThroughCamelCaseField() .Cascade.All(); } } And the listener just asks the auditable object to create log entries so it can update them: internal class AuditEventListener : IPreInsertEventListener, IPreUpdateEventListener { public bool OnPreUpdate(PreUpdateEvent ev) { var audit = ev.Entity as IAuditable; if (audit == null) return false; Log(audit); return false; } public bool OnPreInsert(PreInsertEvent ev) { var audit = ev.Entity as IAuditable; if (audit == null) return false; Log(audit); return false; } private static void LogProperty(IAuditable auditable) { var entry = auditable.CreateAuditEntry(); entry.CreatedAt = DateTime.Now; entry.Who = GetCurrentUser(); // Might potentially execute a query. // Also other information is set for entry here } } The problem with it though is that it throws TransientObjectException when commiting the transaction: NHibernate.TransientObjectException : object references an unsaved transient instance - save the transient instance before flushing. Type: CompanyAudit, Entity: CompanyAudit at NHibernate.Engine.ForeignKeys.GetEntityIdentifierIfNotUnsaved(String entityName, Object entity, ISessionImplementor session) at NHibernate.Type.EntityType.GetIdentifier(Object value, ISessionImplementor session) at NHibernate.Type.ManyToOneType.NullSafeSet(IDbCommand st, Object value, Int32 index, Boolean[] settable, ISessionImplementor session) at NHibernate.Persister.Collection.AbstractCollectionPersister.WriteElement(IDbCommand st, Object elt, Int32 i, ISessionImplementor session) at NHibernate.Persister.Collection.AbstractCollectionPersister.PerformInsert(Object ownerId, IPersistentCollection collection, IExpectation expectation, Object entry, Int32 index, Boolean useBatch, Boolean callable, ISessionImplementor session) at NHibernate.Persister.Collection.AbstractCollectionPersister.Recreate(IPersistentCollection collection, Object id, ISessionImplementor session) at NHibernate.Action.CollectionRecreateAction.Execute() at NHibernate.Engine.ActionQueue.Execute(IExecutable executable) at NHibernate.Engine.ActionQueue.ExecuteActions(IList list) at NHibernate.Engine.ActionQueue.ExecuteActions() at NHibernate.Event.Default.AbstractFlushingEventListener.PerformExecutions(IEventSource session) at NHibernate.Event.Default.DefaultFlushEventListener.OnFlush(FlushEvent event) at NHibernate.Impl.SessionImpl.Flush() at NHibernate.Transaction.AdoTransaction.Commit() As the cascading is set to All I expected NH to handle this. I also tried to modify the collection using state but pretty much the same happens. So the question is what is the last chance to modify object's associations before it gets saved? Thanks, Dmitriy.

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• NSPredicate problem with fetchedResultsController

  - by RyJ

  Please help! I've been trying to figure this out for way too long. I can't seem to use an NSPredicate in my fetchedResultsController method: - (NSFetchedResultsController *)fetchedResultsController { if (fetchedResultsController != nil) return fetchedResultsController; NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"Tweet" inManagedObjectContext:managedObjectContext]; [fetchRequest setEntity:entity]; NSPredicate *predicate = [NSPredicate predicateWithFormat: @"column == 0"]; [fetchRequest setPredicate:predicate]; [fetchRequest setReturnsObjectsAsFaults:NO]; [fetchRequest setFetchBatchSize:20]; NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"created_at" ascending:NO]; NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor, nil]; [fetchRequest setSortDescriptors:sortDescriptors]; NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:managedObjectContext sectionNameKeyPath:nil cacheName:@"Root"]; aFetchedResultsController.delegate = self; self.fetchedResultsController = aFetchedResultsController; [aFetchedResultsController release]; [fetchRequest release]; [sortDescriptor release]; [sortDescriptors release]; return fetchedResultsController; } Yet, in another method, where I simply check to see if an object exists, the predicate works like a charm: - (BOOL)findObjectWithKey:(NSString *)key andValue:(NSString *)value sortBy:(NSString *)sort { NSFetchRequest *request = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"Tweet" inManagedObjectContext:managedObjectContext]; [request setEntity:entity]; NSPredicate *predicate = [NSPredicate predicateWithFormat: @"%K == %@", key, value]; [request setPredicate:predicate]; [request setReturnsObjectsAsFaults:NO]; NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:sort ascending:YES]; NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor, nil]; [request setSortDescriptors:sortDescriptors]; NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:request managedObjectContext:managedObjectContext sectionNameKeyPath:nil cacheName:@"Root"]; aFetchedResultsController.delegate = self; NSError *error = nil; NSArray *result = [managedObjectContext executeFetchRequest:request error:&error]; [aFetchedResultsController release]; [request release]; [sortDescriptor release]; [sortDescriptors release]; if ((result != nil) && ([result count]) && (error == nil)) { return TRUE; } else { return FALSE; }} What am I doing wrong? Thanks in advance!

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• NHibernate, transactions and TransactionScope

  - by Erik

  I'm trying to find the best solution to handle transaction in a web application that uses NHibernate. We use a IHttpModule and at HttpApplication.BeginRequest we open a new session and we bind it to the HttpContext with ManagedWebSessionContext.Bind(context, session); We close and unbind the session on HttpApplication.EndRequest. In our Repository base class, we always wrapped a transaction around our SaveOrUpdate, Delete, Get methods like, according to best practice: public virtual void Save(T entity) { var session = DependencyManager.Resolve<ISession>(); using (var transaction = session.BeginTransaction()) { session.SaveOrUpdate(entity); transaction.Commit(); } } But then this doesn't work, if you need to put a transaction somewhere in e.g. a Application service to include several repository calls to Save, Delete, etc.. So what we tried is to use TransactionScope (I didn't want to write my own transactionmanager). To test that this worked, I use an outer TransactionScope that doesn't call .Complete() to force a rollback: Repository Save(): public virtual void Save(T entity) { using (TransactionScope scope = new TransactionScope()) { var session = Depe.ndencyManager.Resolve<ISession>(); session.SaveOrUpdate(entity); scope.Complete(); } } The block that uses the repository: TestEntity testEntity = new TestEntity { Text = "Test1" }; ITestRepository testRepository = DependencyManager.Resolve<ITestRepository>(); testRepository.Save(testEntity); using (var scope = new TransactionScope()) { TestEntity entityToChange = testRepository.GetById(testEntity.Id); entityToChange.Text = "TestChanged"; testRepository.Save(entityToChange); } TestEntity entityChanged = testRepository.GetById(testEntity.Id); Assert.That(entityChanged.Text, Is.EqualTo("Test1")); This doesn't work. But to me if NHibernate supports TransactionScope it would! What happens is that there is no ROLLBACK at all in the database but when the testRepository.GetById(testEntity.Id); statement is executed a UPDATE with SET Text = "TestCahgned" is fired instead (It should have been fired between BEGIN TRAN and ROLLBACK TRAN). NHibernate reads the value from the level1 cache and fires a UPDATE to the database. Not expected behaviour!? From what I understand whenever a rollback is done in the scope of NHibernate you also need to close and unbind the current session. My question is: Does anyone know of a good way to do this using TransactionScope and ManagedWebSessionContext?

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• Hibernate annotated many-to-one not adding child to parent Collection

  - by Rob Hruska

  I have the following annotated Hibernate entity classes: @Entity public class Cat { @Column(name = "ID") @GeneratedValue(strategy = GenerationType.AUTO) @Id private Long id; @OneToMany(mappedBy = "cat", cascade = CascadeType.ALL, fetch = FetchType.EAGER) private Set<Kitten> kittens = new HashSet<Kitten>(); public void setId(Long id) { this.id = id; } public Long getId() { return id; } public void setKittens(Set<Kitten> kittens) { this.kittens = kittens; } public Set<Kitten> getKittens() { return kittens; } } @Entity public class Kitten { @Column(name = "ID") @GeneratedValue(strategy = GenerationType.AUTO) @Id private Long id; @ManyToOne(cascade = CascadeType.ALL, fetch = FetchType.EAGER) private Cat cat; public void setId(Long id) { this.id = id; } public Long getId() { return id; } public void setCat(Cat cat) { this.cat = cat; } public Cat getCat() { return cat; } } My intention here is a bidirectional one-to-many/many-to-one relationship between Cat and Kitten, with Kitten being the "owning side". What I want to happen is when I create a new Cat, followed by a new Kitten referencing the Cat, the Set of kittens on my Cat should contain the new Kitten. However, this does not happen in the following test: @Test public void testAssociations() { Session session = HibernateUtil.getSessionFactory().getCurrentSession(); Transaction tx = session.beginTransaction(); Cat cat = new Cat(); session.save(cat); Kitten kitten = new Kitten(); kitten.setCat(cat); session.save(kitten); tx.commit(); assertNotNull(kitten.getCat()); assertEquals(cat.getId(), kitten.getCat().getId()); assertTrue(cat.getKittens().size() == 1); // <-- ASSERTION FAILS assertEquals(kitten, new ArrayList<Kitten>(cat.getKittens()).get(0)); } Even after re-querying the Cat, the Set is still empty: // added before tx.commit() and assertions cat = (Cat)session.get(Cat.class, cat.getId()); Am I expecting too much from Hibernate here? Or is the burden on me to manage the Collection myself? The (Annotations) documentation doesn't make any indication that I need to create convenience addTo*/removeFrom* methods on my parent object. Can someone please enlighten me on what my expectations should be from Hibernate with this relationship? Or if nothing else, point me to the correct Hibernate documentation that tells me what I should be expecting to happen here. What do I need to do to make the parent Collection automatically contain the child Entity?

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• Data denormalization and C# objects DB serialization

  - by Robert Koritnik

  I'm using a DB table with various different entities. This means that I can't have an arbitrary number of fields in it to save all kinds of different entities. I want instead save just the most important fields (dates, reference IDs - kind of foreign key to various other tables, most important text fields etc.) and an additional text field where I'd like to store more complete object data. the most obvious solution would be to use XML strings and store those. The second most obvious choice would be JSON, that usually shorter and probably also faster to serialize/deserialize... And is probably also faster. But is it really? My objects also wouldn't need to be strictly serializable, because JsonSerializer is usually able to serialize anything. Even anonymous objects, that may as well be used here. What would be the most optimal solution to solve this problem? Additional info My DB is highly normalised and I'm using Entity Framework, but for the purpose of having external super-fast fulltext search functionality I'm sacrificing a bit DB denormalisation. Just for the info I'm using SphinxSE on top of MySql. Sphinx would return row IDs that I would use to fast query my index optimised conglomerate table to get most important data from it much much faster than querying multiple tables all over my DB. My table would have columns like: RowID (auto increment) EntityID (of the actual entity - but not directly related because this would have to point to different tables) EntityType (so I would be able to get the actual entity if needed) DateAdded (record timestamp when it's been added into this table) Title Metadata (serialized data related to particular entity type) This table would be indexed with SPHINX indexer. When I would search for data using this indexer I would provide a series of EntityIDs and a limit date. Indexer would have to return a very limited paged amount of RowIDs ordered by DateAdded (descending). I would then just join these RowIDs to my table and get relevant results. So this won't actually be full text search but a filtering search. Getting RowIDs would be very fast this way and getting results back from the table would be much faster than comparing EntityIDs and DateAdded comparisons even though they would be properly indexed.

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• Data access pattern

  - by andlju

  I need some advice on what kind of pattern(s) I should use for pushing/pulling data into my application. I'm writing a rule-engine that needs to hold quite a large amount of data in-memory in order to be efficient enough. I have some rather conflicting requirements; It is not acceptable for the engine to always have to wait for a full pre-load of all data before it is functional. Only fetching and caching data on-demand will lead to the engine taking too long before it is running quickly enough. An external event can trigger the need for specific parts of the data to be reloaded. Basically, I think I need a combination of pushing and pulling data into the application. A simplified version of my current "pattern" looks like this (in psuedo-C# written in notepad): // This interface is implemented by all classes that needs the data interface IDataSubscriber { void RegisterData(Entity data); } // This interface is implemented by the data access class interface IDataProvider { void EnsureLoaded(Key dataKey); void RegisterSubscriber(IDataSubscriber subscriber); } class MyClassThatNeedsData : IDataSubscriber { IDataProvider _provider; MyClassThatNeedsData(IDataProvider provider) { _provider = provider; _provider.RegisterSubscriber(this); } public void RegisterData(Entity data) { // Save data for later StoreDataInCache(data); } void UseData(Key key) { // Make sure that the data has been stored in cache _provider.EnsureLoaded(key); Entity data = GetDataFromCache(key); } } class MyDataProvider : IDataProvider { List<IDataSubscriber> _subscribers; // Make sure that the data for key has been loaded to all subscribers public void EnsureLoaded(Key key) { if (HasKeyBeenMarkedAsLoaded(key)) return; PublishDataToSubscribers(key); MarkKeyAsLoaded(key); } // Force all subscribers to get a new version of the data for key public void ForceReload(Key key) { PublishDataToSubscribers(key); MarkKeyAsLoaded(key); } void PublishDataToSubscribers(Key key) { Entity data = FetchDataFromStore(key); foreach(var subscriber in _subscribers) { subscriber.RegisterData(data); } } } // This class will be spun off on startup and should make sure that all data is // preloaded as quickly as possible class MyPreloadingThread { IDataProvider _provider; MyPreloadingThread(IDataProvider provider) { _provider = provider; } void RunInBackground() { IEnumerable<Key> allKeys = GetAllKeys(); foreach(var key in allKeys) { _provider.EnsureLoaded(key); } } } I have a feeling though that this is not necessarily the best way of doing this.. Just the fact that explaining it seems to take two pages feels like an indication.. Any ideas? Any patterns out there I should have a look at?

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• How to add data from an NSTextField to a Core Data Attribute without having to press Return or Tab a

  - by roy-fleming

  I use a sheet with 3 NSTextFields and a Cancel- and OK-Button to edit the attributes of a Core Data Entity. The text entered in the NSTextFields is only updated in the Core Data Entity if i press Tab or Return after writing in the NSTextField or if i focus another NSTextField with the mouse. If i just enter text in an NSTextField and press the OK-Button the entered text is lost. Is there some attribute i can set in Interface Builder to change this NSTextField behaviour?

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• Java Thread Management and Application Flow

  - by user119179

  I have a Java application that downloads information (Entities) from our server. I use a Download thread to download the data. The flow of the download process is as follows: Log in - The user entity is downloaded Based on the User Entity, download a 'Community' entities List and Display in drop down Based on Community drop down selection, Download and show 'Org Tree' in a JTree Based on Node selection, download Category entities and display in drop down Based on Category selection, download Sub Category entities and display in drop down Based on Sub Category selection download a large data set and save it The download occurs in a thread so the GUI does not 'freeze'. It also allows me to update a Progress Bar. I need help with managing this process. The main problem is when I download entity data I have to find a way to wait for the thread to finish before attempting to get the entity and move to the next step in the app flow. So far I have used a modal dialog to control flow. I start the thread, pop up a modal and then dispose of the modal when the thread is finished. The modal/thread are Observer/Observable the thread does a set changed when it is finished and the dialog disposes. Displaying a modal effectively stops the flow of the application so it can wait for the download to finish. I also tried just moving all the work flow to Observers. All relevant GUI in the process are Observers. Each update method waits for the download to finish and then calls the next piece of GUI which does its own downloading. So far I found these two methods produce code that is hard to follow. I would like to 'centralize' this work flow so other developers are not pulling out their hair when they try to follow it. My Question is: Do you have any suggestions/examples where a work flow such as this can be managed in a way that produces code that is easy to follow? I know 'easy' is a relative term and I know my both my options already work but I would like to get some ideas from other coders while I still have time to change it. Thank you very much.

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