I have 3 tables.
users,
campaigns,
links.
They have one-to-many relations. User have many campaigns. Campaign has many links.
I calculate top users by counting the total number of links each user have. So I join 3 tables and group by user and select user and sum(links).
This query involves 3 tables. I have already 3 model class for each of these tables. Now my question is in which model should I put this query? should it go in User model (as I call it top10users? Or there is other way to get this info by utilizing already existing 3 models. I want to know what is most suitable from MVC's point of view.
Additional Information
I am using orm in kohana.
Query:
SELECT u.id,
u.name,
SUM(l.num_visited) total_num_visited
FROM users u
JOIN campaigns c
ON ( u.id = c.user_id )
JOIN links l
ON ( c.id = l.campaign_id )
GROUP BY u.id
ORDER BY total_num_visited DESC
LIMIT 10;
There's no strict reason that your model absolutely has to map 1-to-1 with a table. It may make the most sense in this case to provide a model specifically for Top Users, especially because it is dependent on joining data from several related tables.
Then if there is specific business logic related to Top Users that isn't relevant to the standard User class, you can keep it separated and clean. You can always provide helper / factory methods from TopUser that return instances of User, Campaign, or Link if you need to drill down.
I would say go for topusers(). There is no "correct" answer to this question, not in a technical context. But it should be clearly to understand. So if you want to get top users, why would you put such a method in one of the other models than users? Think of a new team member who gets your code: Where would you look for top users when not in the users model first?
Related
I have a DB, "views," with many, many entries. I also have a "Courses" table, which these views are one-many related to. In Laravel Nova, I can get a metric of all views over time for a course with some code like this:
public function calculate(Request $request)
{
return $this->countByDays($request, view::where('viewable_id', $request->resourceId));
}
In this case, viewable_id is the id of the course, and $request->resourceId gives the ID of the course to sort by. Pretty simple.
However, now things get a little difficult. I have another model called Teachers. Each Teacher can have many courses, also in a one-many relationship. How do I get a metric of views over time for all the courses that teacher teaches?
I assumed the simplest way to do this would be to create a Laravel Collection with all courses the Teacher teaches (not exactly efficient), and then select all views in the database where viewable_id matches one of the courses in that list. Of course, by posting this, I couldn't figure out how to do that.
Of course, once this is figured out, I'd love to do the same thing for Categories (though that should function in a very identical manner to Teachers, so I don't need to ask that question).
How do I get a metric of views over time for all the courses that teacher teaches?
This should be the "countByDays" of views where the viewable_id is in the list of course ids that the teacher teaches.
An SQL query statement to achieve that is given below:
select * from "views"
where "viewable_id" in (select "id" from "courses" where "teacher_id" = ?)
The Eloquent query should be similar to:
$this->countByDays($request,
view::whereIn(
'viewable_id',
Course::with('teacher')
->select('id')
->where('teacher_id', $request->resourceId)
)
);
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 2 tables and I need to join those tables.
I need to select id and name from galleries, where share gal.id = galleries.id and user_id = auth::id().
Tables:
Galleries: id, name
Share: gal_id, user_id
Please show me example in laravel. And I need to display it.
To achieve this, you have Relationship in Eloquent ORM. The official website states :
Of course, your database tables are probably related to one another. For example, a blog post may have many comments, or an order could be related to the user who placed it. Eloquent makes managing and working with these relationships easy. Laravel supports many types of relationships:
You can read all about eloquent relationship over here
If you do not want to use relationship, following is an example on how to join two tables :
DB::table('users')
->select('users.id','users.name','profiles.photo')
->join('profiles','profiles.id','=','users.id')
->where(['something' => 'something', 'otherThing' => 'otherThing'])
->get();
The above query will join two tables namely users and profiles on the basis of user.id = profile.id with two different conditions, you may or may not use where clause, that totally depends on what you are trying to achieve.
This question is about selecting data from multiple tables, joins, Doctrine2, ResultSetMapping, DQL and such stuff.
I have 4 tables:
user
contact
contact_phone
call
With relations as shown on the image: http://i.stack.imgur.com/762Jw.png
Every user can have many contacts, each contact can have many phones and each user can have many calls to/from his contacts. Just like in the real world... I've limited the number of fields in each table just for clarity.
So my problem is that I don't know how exactly to map call numbers to contact names when showing a list of calls for a specific user.
If I want to list all calls of user 1 I do:
$callRepository = $this->getDoctrine()->getRepository('MyBundle:Call');
$calls = $callRepository->findAll(array('user' => 1));
But this will give me just the list of all calls for this user and will not associate number (call.number) with names (contact.name).
I can achieve what I want with plain SQL with this query:
SELECT
c.number,
contact.name
FROM
`call` c
JOIN contact_phone cp ON
cp.number = c.number
JOIN contact ON
contact.id = cp.contact_id
WHERE
c.user_id = contact.user_id
AND c.user_id = 1
Please note that I don't want to select all calls (with SQL) and then map numbers to names with another query from the PHP layer because this way I won't be able to search the calls by name for example.
I was thinking that ResultSetMapping could help me in this case but I have no luck putting the SQL query and the ResultSetMapping together.
Please help,
Thanks!
As per my knowledge, you can acheive by using the below methods. Please go to bottom of the page. you can find Joins... try once..
http://docs.doctrine-project.org/projects/doctrine1/en/latest/en/manual/dql-doctrine-query-language.html
I've done quit a bit of programming with php/mysql on small scale personal projects. However I'm working on my first commercial app that is going to allow customers or businesses to log in and perform CRUD operations. I feel like a total noob asking this question but I have never had to do this before and cannot find any relevant information on the net.
Basically, I've created this app and have a role based system set up on my data base. The problem that I'm running into is how to separate and fetch data for the relevant businesses or groups.
I can't, for example, set my queries up like this: get all records from example table where user id = user id, because that will only return data for that user and not all of the other users that are related to that business. I need a way to get all records that where created by users of a particular business.
I'm thinking that maybe the business should have an id and I should form my queries like this: get all records from example where business id = business id. But I'm not even sure if that's a good approach.
Is there a best practice or a convention for this sort data storing/fetching and grouping?
Note:Security is a huge issue here because I'm storing legal data.
Also, I'm using the latest version of laravel 4 if that's any relevance.
I would like to hear peoples thoughts on this that have encountered this sort problem before and how they designed there database and queries to only get and store data related to that particular business.
Edit: I like to read and learn but cannot find any useful information on this topic - maybe I'm not using the correct search terms. So If you know of any good links pertaining to this topic, please post them too.
If I understand correctly, a business is defined within your system as a "group of users", and your whole system references data belonging to users as opposed to data belonging to a business. You are looking to reference data that belongs to all users who belong to a particular business. In this case, the best and most extensible way to do this would be to create two more tables to contain businesses and business-user relations.
For example, consider you have the following tables:
business => Defines a business entity
id (primary)
name
Entry: id=4, name=CompanyCorp
user => Defines each user in the system
id (primary)
name
Entry: id=1, name=Geoff
Entry: id=2, name=Jane
business_user => Links a user to a particular business
user_id (primary)
business_id (primary)
Entry: user_id=1, business_id=4
Entry: user_id=2, business_id=4
Basically, the business_user table defines relationships. For example, Geoff is related to CompanyCorp, so a row exists in the table that matches their id's together. This is called a relational database model, and is an important concept to understand in the world of database development. You can even allow a user to belong to multiple different companies.
To find all the names of users and their company's name, where their company's id = 4...
SELECT `user`.`name` as `username`, `business`.`name` as `businessname` FROM `business_user` LEFT JOIN `user` ON (`user`.`id` = `business_user`.`user_id`) LEFT JOIN `business` ON (`business`.`id` = `business_user`.`business_id`) WHERE `business_user`.`business_id` = 4;
Results would be:
username businessname
-> Geoff CompanyCorp
-> Jane CompanyCorp
I hope this helps!
===============================================================
Addendum regarding "cases" per your response in the comments.
You could create a new table for cases and then reference both business and user ids on separate columns in there, as the case would belong to both a user and a business, if that's all the functionality that you need.
Suppose though, exploring the idea of relational databases further, that you wanted multiple users to be assigned to a case, but you wanted one user to be elected as the "group leader", you could approach the problem as follows:
Create a table "case" to store the cases
Create a table "user_case" to store case-user relationships, just like in the business_user table.
Define the user_case table as follows:
user_case => Defines a user -> case relationship
user_id (primary)
case_id (primary)
role
Entry: user_id=1, case_id=1, role="leader"
Entry: user_id=2, case_id=1, role="subordinate"
You could even go further and define a table with definitions on what roles users can assume. Then, you might even change the user_case table to use a role_id instead which joins data from yet another role table.
It may sound like an ever-deepening schema of very small tables, but note that we've added an extra column to the user_case relational table. The bigger your application grows, the more your tables will grow laterally with more columns. Trust me, you do eventually stop adding new tables just for the sake of defining relations.
To give a brief example of how flexible this can be, with a role table, you could figure out all the roles that a given user (where user_id = 6) has by using a relatively short query like:
SELECT `role`.`name` FROM `role` RIGHT JOIN `user_case` ON (`user_case`.`role_id` = `role`.`id`) WHERE `user_case`.`user_id` = 6;
If you need more examples, please feel free to keep commenting.