Ok so I have an app that searches through course applications which each belong to an applicant. When I search the applications for a course title it returns the required result set but I would like to sort it by the applicant's date of birth.
How can I do this? I've tried sorting the collection doing $applications->sortBy('applicant.dob') but this seems to just order it by each applicant not the overall collection.
Edit
Here's all of my code... http://laravel.io/bin/PD81z
Any one have an idea how I can approach this?
Thanks!
OK
Your table course and table applicant are actually many-to-many relationship
For this to work, table course_applitions serves as a proxy to link the two table.
see the post, especially the part about many-to-many relationships
http://scotch.io/tutorials/php/a-guide-to-using-eloquent-orm-in-laravel
When fetching results from related tables using the above way, you can always add sort options.
Cheers!
Related
I'm developing a Laravel application right now and this doubt came to me. The proccess is: one customer make one or many requests of some products, then, I can offer one or many deals, based in their product requests.
I created the Product, Request and Deal Laravel models but I need to connect them. I set a many-to-many relationship with Product and Request models through belongsToMany method. My problem is how to set a relationship between Deal and the request. As I said, one deal can contain many request of a product or products.
The structures and relationships of the tables are:
I solved this creating a new model called RequestedProduct referred to "products_requests" table. Also, I dropped the primary key and add an Id attribute to this one.
Also, I need that the composite index (request_id, product_id) doesn't repeat in a row so, i created an unique index.
Heya I am novice web dev or actually I am still in education.
I got this situation Where I have 3 tables lets say : Students, Groups and a join table Student_group.
I put my data from Students in the student model and from groups I put its data in the Group Model so I can use it my application. But I store a date in the Student_group table because I need to know when a student changed from a group.
So my question is in which model do I put this date? Do i need to make a new model for the combined tables or do I need to add another attribute to the student model?
Thanks in advance ;D
That depends. Will the student be in many groups, or one?
If one (one to one relationship), you can decide where to put it. The column could be in either the Student table, or the Student_group. In this case, though, it may be advisable to flatten the data and simply add group columns in your Student table. You decide that as well - if it seems unnecessary to have a join for a one to one relationship (usually it is, not always), then flatten it. In either case, the data should stay in its respective model. That said, you should use the Student model if you handle it in the Student table.
If many (one to many relationship), I'd advise putting it in the Student_group table and leaving it in that model as well.
All in all, the model should be a direct reflection of the data it's representing. You could make some methods inside your Student model to make it easier to get the date, for example. However, I'd personally handle that date inside of the proper model, Student_group. As mentioned, the model should be a direct representation of the data. Again, though, there's nothing wrong with making things a bit easier by creating some methods that help out the developer.
I have a MySQL database set up with a list of all my movies, which I imported from a MS Access database. One field contains the possible values for the genre of the movie, movies can have more than one genre, so I need a data type which supports this feature. In access I could link one table 'genre' to the field 'genre' in my table 'movies', so I could choose none, one ore multiple genres per movie. When I switched to MySQL I used the SET data type to define all the possible values. So far everything is running perfectly.
I am now trying to set up a table in html/php to show the mysql table. I want the table to be able to sort on: title, genre, quality, rating, etc. But for the sorting on genre, I would need the possible values from the set data type. I don't know if it is possible to get the values with some php command/code, but after I lurked around on the web for a while, I didn't see many applications where they use the SET data type for obvious negative reasons.
So I started looking into the Foreign Key possibility. The problem I have here is that -for as far as I know- the key can only contain one possible value, which puts me right back at the start of my problem. I do like the idea of a foreign key, because it would make it way easier for me to add a new genre to the list.
Is there a possibility I am overlooking? Is it possible to either get the values from the SET type to php or to use a foreign key with multiple possibilities for one record?
I know I can also put every genre in my php script manually, but I'd like to have it all on one place. So that if I add a movie with a genre I haven't defined yet, I can just update it at one place and everything else adapts to it.
Dagon is absolutely right here - you have an issue with the structure of the tables in your back end. You are wanting to model a many to many relationship when at the moment with your current back end the best you can do is a one to many relationship.
To review:
You have individual films that can have many genres
And you have individual genres that are related to many films
Relational databases actually don't model many to many relationships with one relationship they use recursion of the one to many relationship and create two joins.
To model a many to many relationship you need three tables
A film table (which I think you already have)
A genre table (which I think you already have)
A junction table which as Dagon suggests will consist of two fields film id and genre id.
You then set up two separate one to many relationships. One from the film table to the junction table and one from the genre table to the junction table.
Now if you want to know all the genres a film is in you simply filter the junction table on the relevant film id and if you want to know all the films with a certain genre you filter the junction table on the genre id.
Set up lookups to relate your genre ids to textual descriptions and bang you are free to change the textual description as much as you want and the great thing if you've done it right it will upgrade every single value in your forms.
This is an absolute fundamental concept of the algebra of sets behind the design of SQL and relational database design.
I would like to have categories, and rankings for my content and users respectively, and I am not sure how to go about implementing this using CakePHP conventions?
Do I need to create a model?
That depends entirely on what these categories are supposed to do and not do. You could simply define a number of constants that you use for categorizing stuff. But, are categories...
subject to change? Do you want to add more eventually?
editable? May you want to change their names?
nested?
supposed to have more attributes than just their id? Names, descriptions?
If you answered Yes to any of the above, you'll want to store them as data in the database. This is independent of Cake, it's just sane data modeling. For Cake that means you'll need to create a model. The same goes for ratings.
So you'll have these tables:
users
hasMany ratings
categories
hasMany contents
contents
belongsTo categories
hasMany ratings
ratings
belongsTo users (polymorphic)
belongsTo contents (polymorphic)
You may want to separate user ratings and content ratings into two tables instead of using a combined polymorphic table (which just means that you have an extra column keeping track of whether a rating is for a user or for content).
i guess you are looking for something like this IF you dont want to use a model:
http://www.dereuromark.de/2010/06/24/static-enums-or-semihardcoded-attributes/
one possible approach to use "enums" for things that maybe only have 1-5 states.
if you have more than 10 or you want to be able to dynamically modify them (label, active/inactive) you will need a separate table and model relation.
So I have a User table and a History table with User hasMany Histories, and I'm trying to implement pagination on the user table.
My problem is that I have search, and some of the things one can search by are things in the History table. Is there a way to filter pagination results based on data in a table associated by hasMany? Containable, which initially seemed like a solution, allows such filtering but only in the retrieval of associated data, not the records themselves (unless I'm missing something?)
Has anyone had to solve this before?
Since it's a hasMany relationship, that means Cake will need to make 2 separate queries: 1 on the users table, and one on the histories table to retrieve all the associations. Since the History data isn't being retrieved until the 2nd query, then your 1st query cannot be filtered via WHERE conditions for fields found in the History model.
To resolve this, you can do one of two things:
Perform pagination on History using Containable (since History belongsTo User, meaning only 1 query will be performed).
Perform pagination on User the way you're already doing, except perform an ad-hoc join to History such that it's no longer a hasMany relationship.
e.g.:
$this->User->bindModel(array('hasOne' => array('History')));
$this->paginate['User']['contain'][] = 'History';
$this->paginate('User', array('History.some_field' => 'some_value'));