Search Results

Search found 1115 results on 45 pages for 'relationships'.

Page 4/45 | < Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >

  • Relationships via Email Rather Than User List

    - by Bob Lerner
    I'm new at Drupal, so I may have missed a solution despite a lot of research: I want users to be able to invite non-users and other users into a named relationship they've set up (using e.g. the Friendlist or User Relationships module) using only email addresses and not the user list. I believe that invitations from both of those modules are done only after the inviter selects the invitee after selecting the invitee from a list of all users. Frankly, I would be surprised if no email solution exists since a large site's user list would be daunting. Does anyone know if this is possible using Organic Groups? Thanks very much.

    Read the article

  • Other link relationships and impact to the SEO

    - by haha
    Example other link relationships <head> <link rel='index' title='Main Title' href='http://domain.com/' /> <link rel='start' title='Part Three' href='http://domain.com/part-3/' /> <link rel='prev' title='Part Two' href='http://domain.com/part-2/' /> <link rel='next' title='Part Four' href='http://domain.com/part-4/' /> </head> Questions Have a big impact to make my site get a nice rank to Search Engine?

    Read the article

  • Representing parent-child relationships in SharePoint lists

    - by Chris Farmer
    I need to create some functionality in our SharePoint app that populates a list or lists with some simple hierarchical data. Each parent record will represent a "submission" and each child record will be a "submission item." There's a 1-to-n relationship between submissions and submission items. Is this practical to do in SharePoint? The only types of list relationships I've done so far are lookup columns, but this seems a bit different. Also, once such a list relationship is established, then what's the best way to create views on this kind of data. I'm almost convinced that it'd be easier just to write this stuff to an external database, but I'd like to give SharePoint a shot in order to take advantage of the automated search capabilities.

    Read the article

  • Chaining Many-To-Many Dimensional Relationships in SSAS

    - by Ray Saltrelli
    I'm developing a cube in SSAS and attempting to model the following relationships: Many Facts to 1 Customer Many Customers to Many Sales Reps Many Sales Reps (Subordinates) to Sales Reps (Managers) Each M2M relationship is facilitated by a bridge table which also acts as a fact table in the cube I have most of this working. I can slice Facts by Customer and by Sales Rep (Subordinate), but when I add Sales Rep (Manager) to the query it appears to return every subordinate/manager combination regardless of whether or not that relationship exists in the bridge table. Any ideas as to what I might be doing wrong?

    Read the article

  • IndexedDB and Relationships

    - by Josh Johnson
    Can I create relationships between my object stores in IndexedDB? For example, I have two object stores: artist and album. An artist has a one-to-many relationship with an album. album.artistId relates the album to artist.id. I'm thinking along the lines of Hibernate here. I would like to do a query for artists and have the albums belonging to that artist returned as an array called artists on the album object. artist.albums = [];

    Read the article

  • LINQ to Entites: Doing a count over one-to-many relationships

    - by chris
    I have a couple of tables where there are one to many relationships. Let's say I have a Country table, a State table with a FK to Country, and a City table with a FK to State. I'd like to be able to create a count of all Cities for a given country, and also a count of cities based on a filter - something like: foreach( var country in Model.Country ) { total = country.State.All().City.All().Count() ; filtered = country.State.All().City.Any(c=>c.field == value).Count(); } Obviously, this doesn't work - is there any way to do this?

    Read the article

  • Entity Framework 4 and 0:1, 0:1 relationships

    - by Eric J.
    I'm using the Model First approach with EF 4 and hit a snag with two tables, Participant (singular because pre-existing from another app) and ActiveParticipants. A Participant may or may not be associated with exactly one ActiveParticipant and vice versa. When I create an association, everything seems to go well on the surface, but then I get a runtime error complaining that Participant does not contain the column ActiveParticipant_Id. It does contain a column ActiveParticipantId (no underscore). When I view the diagram as XML, there's a line like this: <Property Name="ActiveParticipant_Id" Type="uniqueidentifier" Nullable="true" /> Why is it adding an underscore? Is there anything special I need to do for 0:1, 0:1 relationships?

    Read the article

  • Computed Column with relationships

    - by Sethery
    I have a table, MapLocation, which has a column and two relationships with tables that have a field that really need to be displayed as a single concatenated value. I was thinking this was a perfect case for a computed column, but not sure how to go about it. MapLocation MaoNo Section _____________________ _____________________ _____________________ MapNoId MapNoId SectionId SectionId MapNumber (int) Section (int) Identifier (nvarchar) LocationName (nvarchar) LocationName = "MapNUmber - SectionNumber - Identifier" ex: 20 - 03 - SW4 How would I write that? I haven't done much with computed columns or concatenating in SQL. Edit: I need an actual computed column that is automatically updated, im looking for the formula. Or is this more of a function/trigger? Its possible, I certainly barely know what I'm doing. The idea is that I dont want to have to do two more server calls and concatenate these values client side.

    Read the article

  • Problem building relationships between models

    - by Brian Roisentul
    Until now, I've been using acts_as_taggable_on plugin for tagging announcements. That plugin creates the following tables: taggings: relates tags and announcements table(for the tagged item, it has a field called taggable_id, which I rename to "announcement_id" for what I'll explain below). tags: has the tag ids and names. The other day, I discovered that I had no way of getting the announcements tagged with a certain tag, but doing Announcement.tagged_with(tag_name), and I don't want to search by name, but for id. So, as I'm using almost nothing of the functionality in that plugin, I decided to create the models for taggings and tags tables, to accomplish this: Announcement.tags. The models' relationships look as following: class Tagging < ActiveRecord::Base belongs_to :announcement belongs_to :tag end class Tag < ActiveRecord::Base has_many :announcements, :through => :taggings end class Announcement < ActiveRecord::Base has_many :tags, :through => :taggings Why can't I execute the command Announcement.tags? Because when I try, I get undefined method `tags'

    Read the article

  • Ternary (and n-ary) relationships in Hibernate

    - by Bytecode Ninja
    Q 1) How can we model a ternary relationship using Hibernate? For example, how can we model the ternary relationship presented here using Hibernate (or JPA)? Ideally I prefer my model to be like this: class SaleAssistant { Long id; //... } class Customer { Long id; //... } class Product { Long id; //... } class Sale { SalesAssistant soldBy; Customer buyer; Product product; //... } Q 1.1) How can we model this variation, in which each Sale item might have many Products? class SaleAssistant { Long id; //... } class Customer { Long id; //... } class Product { Long id; //... } class Sale { SalesAssistant soldBy; Customer buyer; Set<Product> products; //... } Q 2) In general, how can we model n-ary, n = 3 relationships with Hibernate? Thanks in advance.

    Read the article

  • 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?

    Read the article

  • How to setup relationships in contact Database

    - by Walt
    I am currently embarking on a new venture to learn PHP and MySQL. I have done some simple databases in the past using Access, but this one is to be a web-centric database for tracking a myriad of data including contacts and project information. I will need to link the various tables in various relationships, and I am not sure the best way to do that. Since I am just starting out with PHP/MySQL I am researching online sources for learning as much as possible. If anyone has recommendations on books or websites, I would appreciate it. In setting up my tables, one major area that I am concerned with is contacts. I will have a variety of contacts that include: employees, clients, vendors, subcontractors, etc.. and a single contact can be multiple types and each type would have various additional fields that pertain to them. My thought was to have one contacts table that links to other tables for the various contact types. I'm not sure which field type or setup of table options are best... Thoughts? This scenario will likely play out in other areas of the database as well for projects and products. Any pointers/direction would be appreciated. WES

    Read the article

  • How to properly set relationships in Core Data when using setValue and data already exists

    - by ern
    Let's say I have two objects: Articles and Categories. For the sake of this example all relevant categories have already been added to the data store. When looping through data that holds edits for articles, there is category relationship information that needs to be saved. I was planning on using the -setValue method in the Article class in order to set the relationships like so: - (void)setValue:(id)value forUndefinedKey:(NSString *)key { if([key isEqualToString:@"categories"]){ NSLog(@"trying to set categories..."); } } The problem is that value isn't a Category, it is just a string (or array of strings) holding the title of a category. I could certainly do a lookup within this method for each category and assign it, but that seems inefficient when processing a whole bunch of articles at once. Another option is to populate an array of all possible categories and just filter, but my question is where to store that array? Should it be a class method on Article? Is there a way to pass in additional data to the -setValue method? Is there another, better option for setting the relationship I'm not thinking of? Thanks for your help.

    Read the article

  • Managing Many to Many relationships in asp.net Wizard Control

    - by Luis
    Say I have this entity with a lot of attributes. In the input form I have decided to implement a wizard control so I can collect information about this entity in several steps. The problem is that I need to collect information that has been modeled has many to many relationships. I am planning to use a telerik gridview to manage this (add/edit/delete), the problem is where do I store that data since the entity in a insert form is not created on the database yet. OK so I can store all that info in temporary lists residing in the viewstate, waiting for the final submit where I dump all that in the DB, but one of the steps I am collecting files...now storing files in the viewstate is out of the question, same as as storing them in the session... I have been thinking of implementing in a way that the user has to submit some info first (say first 3 steps), commit the data to the database creating the parent entity and then start inserting all the childs entities...but this will get weird as it's confusing since on the first steps you not saving the data to the DB and on the next ones you are commiting directly... Anyone has any thoughts on this? Thanks

    Read the article

  • derby + hibernate ConstraintViolationException using manytomany relationships

    - by user364470
    Hi, I'm new to Hibernate+Derby... I've seen this issue mentioned throughout the google, but have not seen a proper resolution. This following code works fine with mysql, but when I try this on derby i get exceptions: ( each Tag has two sets of files and vise-versa - manytomany) Tags.java @Entity @Table(name="TAGS") public class Tags implements Serializable { @Id @GeneratedValue(strategy=GenerationType.AUTO) public long getId() { return id; } @ManyToMany(targetEntity=Files.class ) @ForeignKey(name="USER_TAGS_FILES",inverseName="USER_FILES_TAGS") @JoinTable(name="USERTAGS_FILES", joinColumns=@JoinColumn(name="TAGS_ID"), inverseJoinColumns=@JoinColumn(name="FILES_ID")) public Set<data.Files> getUserFiles() { return userFiles; } @ManyToMany(mappedBy="autoTags", targetEntity=data.Files.class) public Set<data.Files> getAutoFiles() { return autoFiles; } Files.java @Entity @Table(name="FILES") public class Files implements Serializable { @Id @GeneratedValue(strategy=GenerationType.AUTO) public long getId() { return id; } @ManyToMany(mappedBy="userFiles", targetEntity=data.Tags.class) public Set getUserTags() { return userTags; } @ManyToMany(targetEntity=Tags.class ) @ForeignKey(name="AUTO_FILES_TAGS",inverseName="AUTO_TAGS_FILES") @JoinTable(name="AUTOTAGS_FILES", joinColumns=@JoinColumn(name="FILES_ID"), inverseJoinColumns=@JoinColumn(name="TAGS_ID")) public Set getAutoTags() { return autoTags; } I add some data to the DB, but when running over Derby these exception turn up (the don't using mysql) Exceptions SEVERE: DELETE on table 'FILES' caused a violation of foreign key constraint 'USER_FILES_TAGS' for key (3). The statement has been rolled back. Jun 10, 2010 9:49:52 AM org.hibernate.event.def.AbstractFlushingEventListener performExecutions SEVERE: Could not synchronize database state with session org.hibernate.exception.ConstraintViolationException: could not delete: [data.Files#3] at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:96) at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66) at org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:2712) at org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:2895) at org.hibernate.action.EntityDeleteAction.execute(EntityDeleteAction.java:97) at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:268) at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:260) at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:184) at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:321) at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:51) at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1206) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:613) at org.hibernate.context.ThreadLocalSessionContext$TransactionProtectionWrapper.invoke(ThreadLocalSessionContext.java:344) at $Proxy13.flush(Unknown Source) at data.HibernateORM.removeFile(HibernateORM.java:285) at data.DataImp.removeFile(DataImp.java:195) at booting.DemoBootForTestUntilTestClassesExist.main(DemoBootForTestUntilTestClassesExist.java:62) I have never used derby before so maybe there is something crutal that i'm missing 1) what am I doing wrong? 2) is there any way of cascading properly when I have 2 many-to-many relationships between two classes? Thanks!

    Read the article

  • Do ORMs normally allow circular relations? If so, how would they handle it?

    - by SeanJA
    I was hacking around trying to make a basic orm that has support for the one => one and one => many relationships. I think I succeeded somewhat, but I am curious about how to handle circular relationships. Say you had something like this: user::hasOne('car'); car::hasMany('wheels'); car::property('type'); wheel::hasOne('car'); You could then do this (theoretically): $u = new user(); echo $u->car->wheels[0]->car->wheels[1]->car->wheels[2]->car->wheels[3]->type; #=> "monster truck" Now, I am not sure why you would want to do this. It seems like it wastes a whole pile of memory and time just to get to something that could have been done in a much shorter way. In my small ORM, I now have 4 copies of the wheel class, and 4 copies of the car class in memory, which causes a problem if I update one of them and save it back to the database, the rest get out of date, and could overwrite the changes that were already made. How do other ORMs handle circular references? Do they even allow it? Do they go back up the tree and create a pointer to one of the parents? DO they let the coder shoot themselves in the foot if they are silly enough to go around in circles?

    Read the article

  • Implementing Unowned relationship Google App Engine

    - by nwallman
    My question is more of a best practices question on how to implement unowned relationships with Google App Engine. I am using JDO to do my persistence and like recommended in the google docs I'm persisting my list of unowned relationships like so: @PersistenceCapable(identityType = IdentityType.APPLICATION) public class User implements Serializable, UserDetails { ... @Persistent private List<Key> groups; ... } Now I came across my predicament when I went to query that list of objects using they Key object. So when I get my list of group keys in order to actually return a list of Group objects I have to do a look up on that key to get the object. My question is what is the recommended way of doing a unowned look up on a model object? Should I have an instance of the PersistanceManagerFactory on my Model object so I can do a lookup? Should I have an instance of my GroupDAO object on my Model object so I can do a look up? Should I have a Utility to do this type of lookup? I'm new to this so I just want to know which is the best way to do this. Thanks.

    Read the article

  • Nullable One To One Relationships with Integer Keys in LINQ-to-SQL

    - by Craig Walker
    I have two objects (Foo and Bar) that have a one-to-zero-or-one relationship between them. So, Foo has a nullable foreign key reference to Bar.ID and a (nullbusted) unique index to enforce the "1" side. Bar.ID is an int, and so Foo.BarID is a nullable int. The problem occurs in the LINQ-to-SQL DBML mapping of .NET types to SQL datatypes. Since int is not a nullable type in .NET, it gets wrapped in a Nullable<int>. However, this is not the same type as int, and so Visual Studio gives me this error message when I try to create the OneToOne Association between them: Cannot create an association "Bar_Foo". Properties do not have matching types: "ID", "BarID". Is there a way around this?

    Read the article

  • Two-way Trust relationship between Samba 3 and AD 2008 R2

    - by Romain
    Did somebody already make a two-way trust relationship between Samba 3 and AD ? I've got Samba 3.5 domain (ES02) controller and AD 2008 R2 domain (ES01) controller. Trust domain seems to be ok: Trusted domains list: ES01 S-1-5-21-1816646249-803782145-3669927669 Trusting domains list: ES01 S-1-5-21-1816646249-803782145-3669927669 I can login AD domain workstation with a Samba user account and access to AD domain workstation shares from Samba workstation with Samba user account. BUT, when I try to access to Samba domain workstation shares from AD domain workstation with AD account (test), I've got this: [2012/12/16 23:00:26.146090, 5] auth/auth.c:268(check_ntlm_password) check_ntlm_password: winbind authentication for user [test] FAILED with error NT_STATUS_NO_SUCH_USER [2012/12/16 23:00:26.146123, 2] auth/auth.c:314(check_ntlm_password) check_ntlm_password: Authentication for user [test] - [test] FAILED with error NT_STATUS_NO_SUCH_USER When I try to access samba share with the Administrator account that I create on both side with same password, I've got this: [2012/12/16 22:57:22.701841, 1] rpc_server/srv_pipe_hnd.c:1602(serverinfo_to_SamInfo_base) _netr_LogonSamLogon: user ES01\Administrator has user sid S-1-5-21-1816646249-803782145-3669927669-500 but group sid S-1-5-21-3405883886-2425668597-4100599511-513. The conflicting domain portions are not supported for NETLOGON calls I don't know if winbind is working because of this: wbinfo -u root nobody smb3user administrator "wbinfo -u" should list all local and trusted users, no ? Any fresh idea would be appreciated, I've been reading all the Internet for 1 week... Regards,

    Read the article

  • Core Data NSPredicate for relationships.

    - by Mugunth Kumar
    My object graph is simple. I've a feedentry object that stores info about RSS feeds and a relationship called Tag that links to "TagValues" object. Both the relation (to and inverse) are to-many. i.e, a feed can have multiple tags and a tag can be associated to multiple feeds. I referred to http://stackoverflow.com/questions/844162/how-to-do-core-data-queries-through-a-relationship and created a NSFetchRequest. But when fetch data, I get an exception stating, NSInvalidArgumentException unimplemented SQL generation for predicate What should I do? I'm a newbie to core data :( I know I've done something terribly wrong... Please help... Thanks -- NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; // Edit the entity name as appropriate. NSEntityDescription *entity = [NSEntityDescription entityForName:@"FeedEntry" inManagedObjectContext:managedObjectContext]; [fetchRequest setEntity:entity]; // Edit the sort key as appropriate. NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"authorname" ascending:NO]; NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor, nil]; [fetchRequest setSortDescriptors:sortDescriptors]; NSEntityDescription *tagEntity = [NSEntityDescription entityForName:@"TagValues" inManagedObjectContext:self.managedObjectContext]; NSPredicate *tagPredicate = [NSPredicate predicateWithFormat:@"tagName LIKE[c] 'nyt'"]; NSFetchRequest *tagRequest = [[NSFetchRequest alloc] init]; [tagRequest setEntity:tagEntity]; [tagRequest setPredicate:tagPredicate]; NSError *error = nil; NSArray* predicates = [self.managedObjectContext executeFetchRequest:tagRequest error:&error]; TagValues *tv = (TagValues*) [predicates objectAtIndex:0]; NSLog(tv.tagName); // it is nyt here... NSPredicate *predicate = [NSPredicate predicateWithFormat:@"tag IN %@", predicates]; [fetchRequest setPredicate:predicate]; // Edit the section name key path and cache name if appropriate. // nil for section name key path means "no sections". NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:managedObjectContext sectionNameKeyPath:nil cacheName:@"Root"]; aFetchedResultsController.delegate = self; self.fetchedResultsController = aFetchedResultsController; --

    Read the article

  • How to apply stereotypes on UML Relationships' MemberEnds?

    - by Cristi Potlog
    I'm running this code on a UML Class Diagram, and it works just fine, but when trying to apply stereotypes from PropertiesEditor in Visual Studio for relationship ends (FirstRole and SecondRole), the stereotypes combo doesn't load even if in code there seems to be applicable stereotypes valid for association properties. What should I put in metaclasses tag in the UML profile except for IProperty? <metaclassMoniker name="/MyUmlProfile/Microsoft.VisualStudio.Uml.Classes.IProperty"/> This is the code: using Microsoft.VisualStudio.Uml.Classes; foreach( IShape shape in currentDiagram.GetSelectedShapes<IElement>() ) { IElement element = shape.GetElement(); foreach( IStereotype stereotype in element.ApplicableStereotypes ) { if( element is Microsoft.VisualStudio.Uml.Classes.IClass ) { IClass classItem = (IClass)element; if( classItem.SuperClasses.Count() > 0 ) { if( stereotype.Name == "SubclassAttribute" ) { element.ApplyStereotype( stereotype ); } } else if( stereotype.Name == "ClassAttribute" ) { element.ApplyStereotype( stereotype ); } } else if( element is Microsoft.VisualStudio.Uml.Classes.IProperty ) { IProperty property = (IProperty)element; if( property.Association != null ) { if( stereotype.Name == "Set" && property.UpperValue != null && property.UpperValue.ToString() == "*" ) { element.ApplyStereotype( stereotype ); } else if( stereotype.Name == "ManyToOne" && ( property.UpperValue == null || property.UpperValue.ToString() == "1" ) ) { element.ApplyStereotype( stereotype ); } } else if( stereotype.Name == "Property" ) { element.ApplyStereotype( stereotype ); } } } }

    Read the article

  • Mapping parent-child relationships with iBatis

    - by agnul
    I have the classic setup public class Parent { Integer id; ... // No generics Collection someCollectionAttribute; ... public void setChildren(Collection c) { ... } } public class Child { Integer id; ... } and I'm trying to map this on the usual table setup using iBatis (version 2.30... don't ask). create table parents ( ID integer primary key ... ) create table children ( ID integer primary key PARENT_ID integer references parents(id) ... ) My mapping file looks like this <resultMap id="ParentResult" groupBy="id"> <result property="id" column="ID" /> ... <result property="children" resultMap="ChildResult" /> </resultMap> <resultMap id="ChildResult"> <result property="id" column="ID" /> <result property="parentId" column="PARENT_ID" /> ... </result> <sql id="loadParent" resultMap="ParentResult"> select P.ID as p1, ..., C.ID as c1, C.PARENT_ID as c2 ... from parents P join children C on (P.ID = C.PARENT_ID) where P.ID = #id# order by P.ID </sql> Doing the usual sqlMap.queryForObject("loadParent", new Integer(42)) at first caused a NullPointerException inside the setChildren setter which apparently is called with a null argument (my bad). Fixing the setter everything works fine, but the logs show that setChildren is called only once before even running a single SQL statement, still with a null argument, so I'm wondering what's going on here. Anyone has any clues?

    Read the article

  • Sql Querying, group relationships

    - by Jordan
    Hi, Suppose I have two tables: Group ( id integer primary key, someData1 text, someData2 text ) GroupMember ( id integer primary key, group_id foreign key to Group.id, someData text ) I'm aware that my SQL syntax is not correct :) Hopefully is clear enough. My problem is this: I want to load a group record and all the GroupMember records associated with that group. As I see it, there are two options. A single query: SELECT Group.id, Group.someData1, Group.someData2 GroupMember.id, GroupMember.someData FROM Group INNER JOIN GroupMember ... WHERE Group.id = 4; Two queries: SELECT id, someData2, someData2 FROM Group WHERE id = 4; SELECT id, someData FROM GroupMember WHERE group_id = 4; The first solution has the advantage of only being one database round trip, but has the disadvantage of returning redundant data (All group data is duplicated for every group member) The second solution returns no duplicate data but involves two round trips to the database. What is preferable here? I suppose there's some threshold such that if the group sizes become sufficiently large, the cost of returning all the redundant data is going to be greater than the overhead involved with an additional database call. What other things should I be thinking about here? Thanks, Jordan

    Read the article

  • Rails accepts_nested_attributes_for and build_attribute with polymorphic relationships

    - by SooDesuNe
    The core of this question is where build_attribute is required in a model with nested attribuites I'm working with a few models that are setup like: class Person < ActiveRecord::Base has_one :contact accepts_nested_attributes_for :contact, :allow_destroy=> true end class Contact < ActiveRecord::Base belongs_to :person has_one :address, :as=>:addressable accepts_nested_attributes_for :address, :allow_destroy=> true end class Address < ActiveRecord::Base belongs_to :addressable, :polymorphic=>true end I have to define the new method of people_controller like: def new @person = Person.new @person.build_contact @person.contact.build_address #!not very good encapsulation respond_to do |format| format.html # new.html.erb format.xml { render :xml => @person } end end Without @person.contact.build_address the address relationship on contact is NIL. I don't like having to build_address in people_controller. That should be handled by Contact. Where do I define this in Contact since the contacts_controller is not involved here?

    Read the article

< Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >