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  • Entity Framework 4 / POCO - Where to start?

    - by Basiclife
    Hi, I've been programming for a while and have used LINQ-To-SQL and LINQ-To-Entities before (although when using entities it has been on a Entity/Table 1-1 relationship - ie not much different than L2SQL) I've been doing a lot of reading about Inversion of Control, Unit of Work, POCO and repository patterns and would like to use this methodology in my new applications. Where I'm struggling is finding a clear, concise beginners guide for EF4 which doesn't assume knowledge of EF1. The specific questions I need answered are: Code first / model first? Pros/cons in regards to EF4 (ie what happens if I do code first, change the code at a later date and need to regenerate my DB model - Does the data get preserved and transformed or dropped?) Assuming I'm going code-first (I'd like to see how EF4 converts that to a DB schema) how do I actually get started? Quite often I've seen articles with entity diagrams stating "So this is my entity model, now I'm going to ..." - Unfortunately, I'm unclear if they're created the model in the designer, saved it to generate code then stopped any further auto-code generation -or- They've coded (POCO)? classes and the somehow imported them into the deisgner view? I suppose what I really need is an understanding of where the "magic" comes from and how to add it myself if I'm not just generating an EF model directly from a DB. I'm aware the question is a little vague but I don't know what I don't know - So any input / correction / clarification appreciated. Needless to say, I don't expect anyone to sit here and teach me EF - I'd just like some good tutorials/forums/blogs/etc. for complete entity newbies Many thanks in advance

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  • What is a good motivating example for dataflow concurrency?

    - by Alex Miller
    I understand the basics of dataflow programming and have encountered it a bit in Clojure APIs, talks from Jonas Boner, GPars in Groovy, etc. I know it's prevalent in languages like Io (although I have not studied Io). What I am missing is a compelling reason to care about dataflow as a paradigm when building a concurrent program. Why would I use a dataflow model instead of a mutable state+threads+locks model (common in Java, C++, etc) or an actor model (common in Erlang or Scala) or something else? In particular, while I know of library support in the languages above (and Scala and Ruby), I don't know of a single program or library that is a poster child user of this model. Who is using it? Why do they find it better than the other models I mentioned?

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  • acts-as-taggable-on find within specific tag context

    - by user284194
    I have two models (entries and messages) using acts-as-taggable-on for tagging. How do I write a find condition for tagged messages from only the one model and not both? The only way I can get the tagged items to display is through the basic find: @tags = Tag.find(:all) But this displays tags from both the entries model and the messages model. How can I find the tags from just the messages model? I'm really new to Rails and ActiveRecord finds. I appreciate any help you can offer. Thank you for reading my question.

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  • How to efficiently show many Images? (iPhone programming)

    - by Thomas
    In my application I needed something like a particle system so I did the following: While the application initializes I load a UIImage laserImage = [UIImage imageNamed:@"laser.png"]; UIImage *laserImage is declared in the Interface of my Controller. Now every time I need a new particle this code makes one: // add new Laserimage UIImageView *newLaser = [[UIImageView alloc] initWithImage:laserImage]; [newLaser setTag:[model.lasers count]-9]; [newLaser setBounds:CGRectMake(0, 0, 17, 1)]; [newLaser setOpaque:YES]; [self.view addSubview:newLaser]; [newLaser release]; Please notice that the images are only 17px * 1px small and model.lasers is a internal array to do all the calculating seperated from graphical output. So in my main drawing loop I set all the UIImageView's positions to the calculated positions in my model.lasers array: for (int i = 0; i < [model.lasers count]; i++) { [[self.view viewWithTag:i+10] setCenter:[[model.lasers objectAtIndex:i] pos]]; } I incremented the tags by 10 because the default is 0 and I don't want to move all the views with the default tag. So the animation looks fine with about 10 - 20 images but really gets slow when working with about 60 images. So my question is: Is there any way to optimize this without starting over in OpenGl ES? Thank you very much and sorry for my english! Greetings from Germany, Thomas

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  • How do I use namespaces in Backbone with RequireJs

    - by dev.pus
    I am unsure how I use namespaces in an modularized (RequireJs) Backbone environment. I have thought a bit how it could look like but am totally unsure if this is the right way. app.js (getting executed by main.js) define('App', ['underscore', 'backbone', 'Router'], function( _, Backbone, Router){ function initialize(){ var app = {}; // app is the global namespace variable, every module exists in app app.router = new Router(); // router gets registered Backbone.history.start(); } return { initialize: initialize } }); messages.js define('MessageModel', ['underscore', 'backbone', 'App'], function(_, Backbone, App){ App.Message.Model; // registering the Message namespace with the Model class App.Message.Model = Backbone.Model.extend({ // the backbone stuff }); return App; }); Is this the right approach or am I fully on the wrong way (if yes please correct me!)

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  • JSON serialization of Google App Engine models

    - by user111677
    I've been search for quite a while with no success. My project isn't using Django, is there a simple way to serialize App Engine models (google.appengine.ext.db.Model) into JSON or do I need to write my own serializer? My model class is fairly simple. For instance: class Photo(db.Model): filename = db.StringProperty() title = db.StringProperty() description = db.StringProperty(multiline=True) date_taken = db.DateTimeProperty() date_uploaded = db.DateTimeProperty(auto_now_add=True) album = db.ReferenceProperty(Album, collection_name='photo') Thanks in advance.

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  • HABTM and belongsTo at the same join, cakePhp

    - by Cynthia
    Hello everyone. I have a model Fix with a relationship HABTM Device model. Device model has a belongsTo to Device_type model, like this, for only getting the device type name: var $belongsTo = array('Device_type'=>array('fields'=>'name')); So, I need every Fix, its devices and its Device_types. When I make a Fix->find('all', array('recursive' => 2)) I expect to get every Device related to Fix (this works ok) and ALSO for every device, its Device_type.name (which is not working). This is what I get instead for every Device in the result (an empty array): ["Device_type"]=> array(0) { } Besides this, when I make this query for testing: Fix->Device->find('all'), it returns the current Device_type.names for every device related to fixes, which means models are related propertly. Any help? Thanks.

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  • django admin how to limit selectbox values

    - by SledgehammerPL
    model: class Store(models.Model): name = models.CharField(max_length = 20) class Admin: pass def __unicode__(self): return self.name class Stock(Store): products = models.ManyToManyField(Product) class Admin: pass def __unicode__(self): return self.name class Product(models.Model): name = models.CharField(max_length = 128, unique = True) parent = models.ForeignKey('self', null = True, blank = True, related_name='children') (...) def __unicode__(self): return self.name mptt.register(Product, order_insertion_by = ['name']) admin.py: from bar.drinkstore.models import Store, Stock from django.contrib import admin admin.site.register(Store) admin.site.register(Stock) Now when I look at admin site I can select any product from the list. But I'd like to have a limited choice - only leaves. In mptt class there's function: is_leaf_node() -- returns True if the model instance is a leaf node (it has no children), False otherwise. But I have no idea how to connect it I'm trying to make a subclass: in admin.py: from bar.drinkstore.models import Store, Stock from django.contrib import admin admin.site.register(Store) class StockAdmin(admin.ModelAdmin): def queryset(self, request): qs = super(StockAdmin, self).queryset(request).filter(ihavenoideawhatfilter) admin.site.register(Stock, StockAdmin) but I'm not sure if it's right way, and what filter set.

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  • Can a grails controller extend from a base class? How to make it so grails doesn't blow up?

    - by egervari
    I wrote a base class to help build my controllers more quickly and to remove duplication. It provides some helper methods, default actions and some meta programming to make these things easier to build. One of those methods in the base class is like this: def dynamicList(Class clazz) { def model = new LinkedHashMap() model[getMapString(clazz) + "s"] = list(clazz) model[getMapString(clazz) + "sTotal"] = count(clazz) model } The action that calls it, also in the base class, is this: def list = { dynamicList(clazz) } Unfortunately, when I go to list action in the controller subclass that inherits the base class when my application is deployed, I get this exception: groovy.lang.MissingMethodException: No signature of method: groovy.lang.MissingMethodException.dynamicList() is applicable for argument types: (java.lang.Class) values: [class project .user.User] at project.user.UserController$_closure1.doCall(UserController.groovy:18) at project.user.UserController$_closure1.doCall(UserController.groovy) at java.lang.Thread.run(Thread.java:619) How can I hit grails over the head and just tell it do what I want it to do? My controller unit tests run just fine, so grails' run-time is totally at fault :/ Ken

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  • Rails: Helpers and Models - where to organize code

    - by Sam
    More and more I'm putting all of my code in models and helpers concerning MVC. However, sometimes I'm not sure where to organize code. Should it go into the model or should it go into a helper. What are the benefits of each. Is one faster or are they the same. I've heard something about all models getting cached so it seems then like that would be a better place to put most of my code. For example here is a scenario that works in a model or in helper: def status if self.purchased "Purcahsed" elsif self.confirmed "Confirmed" elsif self.reserved "Reserved" else "Pending" end end I don't need to save this status as in the database because there are boolean fields for purchased, and confirmed, and reserved. So why put this in a model or why put it into a helper? So I'm not sure of the best practice or benefits gained on putting code into a model or into helper if it can be in both.

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  • Core Data Inferred Migration – Automatic "lightweight" vs Manual

    - by ohhorob
    I've updated the model of an existing iPhone app in some simple ways (remove attribute, add attribute, remove index), and can use automatic lightweight migration to migrate the persistent store. Due to the typical size of the data set, the processing time is not insignificant, and warrants feedback for the user. NSMigrationManager provides a simple but useful migrationProgress value that sends KVO notifications as the migration is performed. That forms the basis of providing feedback, however attempting to use an inferred model ([NSMappingModel inferredMappingModelForSourceModel:destinationModel:error:]) results in drastically different timing for the exact same dataset. Profile results on and original iPhone (2G) Automatic inferred lightweight migration PROFILE: CacheManager -migrateStore PROFILE: 0.6130 (+0.6130) models loaded PROFILE: 1.1759 (+0.5629) delegate -CacheManagerWillMigrate: PROFILE: 1.2516 (+0.0757) persistent store coordinator loaded PROFILE: 5.1436 (+3.8920) automatic lightweight migration completed PROFILE: 5.5435 (+0.3999) delegate -CacheManagerDidFinishMigration:withError: Manual inferred migration PROFILE: CacheManager -migrateStore PROFILE: 0.6660 (+0.6660) models loaded PROFILE: 1.1471 (+0.4811) inferred mapping model generated PROFILE: 1.4046 (+0.2574) delegate -CacheManagerWillMigrate: PROFILE: 1.5058 (+0.1013) persistent store coordinator loaded PROFILE: 22.6952 (+21.1894) manual migration completed PROFILE: 23.1478 (+0.4525) delegate -CacheManagerDidFinishMigration:withError: So, with an inferred model, the manual migration takes over 5 times longer than automatic! It's a big inconsistency, and the lightweight option that NSPersistentStoreCoordinator -addPersistentStoreWithType:configuration:URL:options:error: provides absolutely no indication of progress while processing. Can anybody provide a supported way to get the migrationProgress values during automatic migration, OR a way to configure an inferred mapping model to be as fast during manual processing as automatic?

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  • How to add a rich text box or use html and links in asp.net mvc 2?

    - by VJ
    Hi all I wanted to allow the users to enter html and links in textbox. How can I achieve something like this in ASP.NET MVC 2? I have something like this now... <div class="editor-field"> <%= Html.TextAreaFor(model => model.Description) %> <%= Html.ValidationMessageFor(model => model.Description) %> </div> I found this link - http://stackoverflow.com/questions/2238393/allow-html-in-text-boxes-asp-net-mvc But I am using ASP.NET MVC 2 and I am looking for something that MVC provides for this by default like a rich textbox or something and not just disable the validation.

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  • problem in basic implementation of MVVM pattern - Services

    - by netmajor
    I watch some video and read articles about MVVM pattern and start thinking how should I implement it in my Silverlight app. So at first I create Silverlight application. I think that for clear view I create 3 folders: View - for each user control page in my app, ViewModel - for c# class which will querying date and Model- Entity Data Model of my SQL Server or Oracle Database. And now I am confused, cause I want to implement *WCF/RIA Services/Web services* in my project. In which folder should I put in class of services? I see in examples that Services take date and filtering it and then output data was binding in View - so It looks as ViewModel. But I was sure that someone use Services in Model and that I want to do. But how? Can someone explain me implementing Services as Model? Is my point of view at MVVM is correctly?

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  • Django - how to write users and profiles handling in best way?

    - by SpankMe
    Hey, I am writing simple site that requires users and profiles to be handled. The first initial thought is to use django's build in user handling, but then the user model is too narrow and does not contain fields that I need. The documentation mentions user profiles, but user profiles section has been removed from djangobook covering django 1.0 (ideally, the solution should work with django 1.2), and the Internet is full of different solutions, not making the choice easier (like user model inheritance, user profiles and django signals, and so on). I would like to know, how to write this in good, modern, fast and secure way. Should I try to extend django builtin user model, or maybe should I create my own user model wide enough to keep all the information I need? Below you may find some specifications and expectations from the working solution: users should be able to register and authenticate every user should have profile (or model with all required fields) users dont need django builtin admin panel, but they need to edit their profiles/models via simple web form Please, let me know how do you solve those issues in your applications, and what is the best current way to handle users with django. Any links to articles/blogs or code examples are highly appreciated!

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  • MVVM Binding Orthogonal Aspects in Views e.g. Application Settings

    - by chibacity
    I have an application which I am developing using WPF\Prism\MVVM. All is going well and I have some pleasing MVVM implementations. However, in some of my views I would like to be able to bind application settings e.g. when a user reloads an application, the checkbox for auto-scrolling a grid should be checked in the state it was last time the user used the application. My view needs to bind to something that holds the "auto-scroll" setting state. I could put this on the view-model, but applications settings are orthogonal to the purpose of the view-model. The "auto-scroll" setting is controlling an aspect of the view. This setting is just an example. There will be quite a number of them and splattering my view-models with properties to represent application settings (so I can bind them) feels decidedly yucky. One view-model per view seems to be de rigeuer... What is best\usual practice here? Splatter my view-models with application settings? Have multiple view-models per view so settings can be represented in their own right? Split views so that controls can bind to an ApplicationSettingsViewModel? = too many views? Something else? Edit 1 To add a little more context, I am developing a UI with a tabbed interface. Each tab will host a single widget and there a variety of widgets. Each widget is a Prism composition of individual views. Some views are common amongst widgets e.g. a file picker view. Whilst each widget is composed of several views, as a whole, conceptually a widget has a single set of user settings e.g. last file selected, auto-scroll enabled, etc. These need to be persisted and retrieved\applied when the application starts again, and the widget views are created. My question is focused on the fact that conceptually a widget has a single set of user settings which is at right-angles to the fact that a widget consists of many views. Each view in the widget has it's own view-model (which works nicely and logically) but if I stick to a one view-model per view, I would have to splatter each view-model with user settings appropriate to it. This doesn't sound right ?!?

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  • a question about rails general practice with REST, json, and ajax

    - by Nik
    Hi all, I have this question concerning REST I think: I have read a few rest tutorials and the feeling I get from them is that each action in a restful controller tends to be lean and almost single purpose: "Index gives off a collection of a model show gives off one model edit/new a prep place for changing/create a model update/create changes and makes new model deletes removes one model" After reading all these tutorials, rest seems to be to be a means to create an interface for a model, much like active resource type of thing. the mantra seems to be "controller provides data and data only and is also pretty convention over configuration, so expect projects_path to return a bunch of projects" I can understand that, and I like the cleanliness. But here's when I run into some trouble in reality in applying these guidelines: say three models, Project with attrib title, User with attrib name, and Location with attrib address. Say in views/users/index.html.erb, I want to use Ajax to fetch and display a project in a div#project_display when the user clicks on a project element, I know that I can use views/projects/show.js.rjs like this: page.replace_html 'project_display' "#{@project.name}" where in the projects_controller.rb def show @project = Project.find(params[:id]) repsond_to do |format| format.js and other formats... end end I have no problem in doing that for a couple of years now. BUT doesn't that mean that my JS response for the project#show action is LOCkED to present data to div#project_display element and show only whatever I that rjs template says it should show? That's very limiting and doesn't sound very "interface" like. I have never used JSON before or much XML, so I thought, maybe the JS response should send back raw stuff, like JSON and somehow the page on which the ajax request was called has the instruction on what do to with these raw data. That sounds a lot more flexible, doesn't it? Because look back at that exmpale, what if in the views/locations/index.html.erb, I want to do the exact same thing except I want to put the response in div#project_goes_here and the response should be #{project.name} I know this is a trivial change but that's the point: the RJS only allows one template at a time. So I think the JSON route is the way to go, but how does the already loaded page, the one that the ajax call came from, know when or how to "look forward" to incoming data? I read that PrototypeJS has this template thing, I wouldn't mind using it with JSON, but if you can demonstrate this or other means for displaying received-from-ajax data, I am all attention. Thank You

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  • Rails 3 nested forms with has_many :through, entry in join table dosen't get deleted after update

    - by Hadi S.
    Hi, i have a 'User' model which has a has_many relationship to a 'Number' model through a join table 'user_number' model. I use accepts_nested_attributes_for :numbers, :allow_destroy = true in the 'User' model. Everything works fine except that whenever i delete a number from a user in the edit form, the associated number is deleted correctly in the 'number' table, but not the entry in the 'user_number' join table. In the update controller action i only use this: ... if @user.update_attributes(params[:user]) ... How can i force rails to also delete the associated entry in the join table?

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  • acts_as_xapian jobs table

    - by Grnbeagle
    Hi, Can someone explain to me the inner workings of acts_as_xapian_jobs table? I ran into an issue with the acts_as_xapian plugin recently, where I kept getting the following error when it creates an object with xapian indexed fields: Mysql::Error: Duplicate entry 'String-2147483647' for key 2: INSERT INTO `acts_as_xapian_jobs` (`action`, `model`, `model_id`) VALUES ('update', 'String', 23730251831560) It turns out the model_id exceeded the max int value of 2147483647. The workaround was to update model_id to use bigint. Why would the model_id be so huge? By looking at content of acts_as_xapian_jobs, it seems it creates a row for every field that is being indexed.. Understanding how a job gets created in the table would help a great deal. Here's a sampling of the table: mysql> select * from acts_as_xapian_jobs limit 5\G *************************** 1. row *************************** id: 19 model: String model_id: 23804037900560 action: update *************************** 2. row *************************** id: 49 model: String model_id: 23804037191200 action: update *************************** 3. row *************************** id: 79 model: String model_id: 23804037932180 action: update *************************** 4. row *************************** id: 109 model: String model_id: 23804037101700 action: update *************************** 5. row *************************** id: 139 model: String model_id: 23804037722160 action: update Thanks in advance, Amie

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  • Django loaddata throws ValidationError: [u'Enter a valid date in YYYY-MM-DD format.'] on null=true f

    - by datakid
    When I run: django-admin.py loaddata ../data/library_authors.json the error is: ... ValidationError: [u'Enter a valid date in YYYY-MM-DD format.'] The model: class Writer(models.Model): first = models.CharField(u'First Name', max_length=30) other = models.CharField(u'Other Names', max_length=30, blank=True) last = models.CharField(u'Last Name', max_length=30) dob = models.DateField(u'Date of Birth', blank=True, null=True) class Meta: abstract = True ordering = ['last'] unique_together = ("first", "last") class Author(Writer): language = models.CharField(max_length=20, choices=LANGUAGES, blank=True) class Meta: verbose_name = 'Author' verbose_name_plural = 'Authors' Note that the dob DateField has blank=True, null=True The json file has structure: [ { "pk": 1, "model": "books.author", "fields": { "dob": "", "other": "", "last": "Carey", "language": "", "first": "Peter" } }, { "pk": 3, "model": "books.author", "fields": { "dob": "", "other": "", "last": "Brown", "language": "", "first": "Carter" } } ] The backing mysql database has the relevent date field in the relevant table set to NULL as default and Null? = YES. Any ideas on what I'm doing wrong or how I can get loaddata to accept null date values?

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  • NSEntityDescription entityForName returning nil

    - by Kamchatka
    Hi, I did some changes to my model (but I don't want migration yet, so I just remove the application, built clean etc.) so my application works in the simulator. However, when I run it on the iPhone, I get the following error: *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'executeFetchRequest:error: A fetch request must have an entity.' I set the entity like this: NSEntityDescription *entity = [NSEntityDescription entityForName:@"Document" inManagedObjectContext:managedObjectContext]; My managedObjectContext is not nil. But I suspect that it doesn't load the object model correctly or something similar because If I display the entities in the model, the list is empty. How can I make sure the model is loaded? Thanks,

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  • Website settings for running visual web as root?

    - by Curtis White
    Scott Gu explains how to run visual web developer using a root path, here: http://weblogs.asp.net/scottgu/archive/2006/12/19/tip-trick-how-to-run-a-root-site-with-the-local-web-server-using-vs-2005-sp1.aspx This worked exactly as he described in one instance for me. But, today I do not see this option. More over, I do not think I have a solution file, and I think that has something to do with it. I'm aware there are web application projects and web site model, and web site model is basically just a "directory". But can web site model, also, have a solution file for this setting or not a solution file? What determines that? I am interested in using this method on on a web site, i.e directory only model.

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  • django left join with null

    - by SledgehammerPL
    The model: class Product(models.Model): name = models.CharField(max_length = 128) def __unicode__(self): return self.name class Receipt(models.Model): name = models.CharField(max_length=128) components = models.ManyToManyField(Product, through='ReceiptComponent') class Admin: pass def __unicode__(self): return self.name class ReceiptComponent(models.Model): product = models.ForeignKey(Product) receipt = models.ForeignKey(Receipt) quantity = models.FloatField(max_length=9) unit = models.ForeignKey(Unit) def __unicode__(self): return unicode(self.quantity!=0 and self.quantity or '') + ' ' + unicode(self.unit) + ' ' + self.product.genitive The idea: there are a components on stock. I'd like to find out which recipes I can made with components which I have. It's not easy - but possible - I made a SQL view, which gets the solution. But I'm learning python and Django so I'd like to make it Django-style ;D The concept of solution: get the set of recipes which has at last one component: list_of_available_components = ReceiptComponent.objects.filter(product__in=list_of_available_products).distinct() list_of_related_receipts = Receipt.objects.filter(receiptcomponent__in = list_of_available_components).distinct() get recipes (from list_of_related_receipts) which has not at last one component list_of_incomplete_recipes = (SELECT * FROM drinkbook_receiptcomponent LEFT JOIN drinkstore_stock_products USING(product_id) WHERE drinkstore_stock_products.stock_id IS NULL AND receipt_id IN (SELECT receipt_id FROM drinkbook_receiptcomponent JOIN drinkstore_stock_products USING(product_id))) get recipes (from list_of_related_receipts) which are not in "list_of_incomplete_recipes"

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  • Serialized form fields in Ruby on Rails problem

    - by Violet
    I'm having a problem making serialized columns in my model persist correctly in forms. If my model validation fails I want to redisplay the "new" page with all my model data still in the forms. Right now, everything except the serialized fields seem to persist (if my Order fails to purchase, on the "new" page the email is still filled in but the shipping address fields are not). Is this a Rails bug or am I doing something wrong? My model: class Order < ActiveRecord::Base serialize :shipping_address end My controller: def new @order = Order.new end def create @order = Order.new params[:order] if @order.purchase then render :action => "success" else render :action => "new" end end My view, new.html.haml: = form_for @order do |f| - if @order.errors.any? #errorExplanation %p The following errors occurred: %ul - for msg in @order.errors.full_messages %li= msg %h2 Billing Information = f.label :email = f.text_field :email %h2 Shipping Address = f.fields_for :shipping_address do |b| %p.field.address = b.label :address1 = b.text_field :address1 %p= f.submit "Place Order"

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  • MapReduce for counting parameter values

    - by cnkt
    I have document like this: { "_id": ObjectId("4d17c7963ffcf60c1100002f"), "title": "Text", "params": { "brand": "BMW", "model": "i3" } } { "_id": ObjectId("4d17c7963ffcf60c1100002f"), "title": "Text", "params": { "brand": "BMW", "model": "i5" } } What i need is the count of every params values. like: brand --------- BMW (2) model --------- i3 (1) i5 (1) I think i have to write map/reduce functions. How can i do this? Thanks.

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  • Schema-less design guidelines for Google App Engine Datastore and other NoSQL DBs

    - by jamesaharvey
    Coming from a relational database background, as I'm sure many others are, I'm looking for some solid guidelines for setting up / designing my datastore on Google App Engine. Are there any good rules of thumb people have for setting up these kinds of schema-less data stores? I understand some of the basics such as denormalizing since you can't do joins, but I was wondering what other recommendations people had. The particular simple example I am working with concerns storing searches and their results. For example I have the following 2 models defined in my Google App Engine app using Python: class Search(db.Model): who = db.StringProperty() what = db.StringProperty() where = db.StringProperty() createDate = db.DateTimeProperty(auto_now_add=True) class SearchResult(db.Model): title = db.StringProperty() content = db.StringProperty() who = db.StringProperty() what = db.StringProperty() where = db.StringProperty() createDate = db.DateTimeProperty(auto_now_add=True) I'm duplicating a bunch of properties between the models for the sake of denormalization since I can't join Search and SearchResult together. Does this make sense? Or should I store a search ID in the SearchResult model and effectively 'join' the 2 models in code when I retrieve them from the datastore? Please keep in mind that this is a simple example. Both models will have a lot more properties and the way I'm approaching this right now, I would put any property I put in the Search model in the SearchResult model as well.

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