i'm trying to get extra column as foreign key in laravel many to many relationship..here is my table structure
idcards
id,
name,
quality
id,
name
idcard_quality
id,
idcard_id
quality_id
related_id
in above idcard_quality table i want add extra foreign key related_id, i wanted to retrieve result like every idcard hasmany qualities and that quality is another idcard.. suppose one idcardcard has one normal quality and that normal quality is different idcard...
please help me
I think your table design should look like this:
idcards
id,
name
quality
id,
name,
related_id
idcard_quality
idcard_id
quality_id
This way when you retrieve the values of the parent/related id card on joining the tables.
Related
This is more of a best practices question. I am making a game where factions can upgrade their technology for their faction. So I have a faction table which stores the faction name and id and a tech_upgrades table which stores the possible tech upgrades along with their costs. Then I have another table which stores the progress each faction has made towards their tech upgrades which is the faction_tech_upgrades table. So there should be a row in faction_tech_upgrades for every combination of faction and tech_upgrade. This kind of looks like a pivot table with extra data similar to https://laravel.com/docs/9.x/eloquent-relationships#retrieving-intermediate-table-columns
My dilemma involves how to set up the eloquent relationships. My gut says to use option 1 but just wanted to make sure I'm not setting these up poorly. So any advice on best practices is appreciated. Here are the 2 options I think make sense.
Option 1:
Create a model for faction_tech_upgrades. Then set up a one to many relationship between factions and faction_tech_upgrades, and set up a one to many relationship between tech_upgrades and faction_tech_upgrades. The reasoning here is that the faction_tech_upgrades table is functioning as more than just a pivot table so maybe making a model for it makes sense, as it might be easier to work with in terms of updating and querying the table.
Option 2:
Set faction_tech_upgrades up a as a pivot table and use the above link to get the data from that table. And use https://laravel.com/docs/9.x/eloquent-relationships#updating-a-record-on-the-intermediate-table to update the table.
factions columns
id,
name,
color,
created_at,
updated_at
tech_upgrades columns
id,
name,
description,
class,
order,
type,
gold_cost,
iron_cost,
wood_cost,
emerald_cost,
pink_tourmaline_cost,
turquoise_cost,
created_at,
updated_at
faction_tech_upgrades columns
id,
faction_id,
tech_upgrade_id,
unlocked,
gold_contributed,
iron_contributed,
wood_contributed,
emerald_contributed,
pink_tourmaline_contributed,
turquoise_contributed,
created_at,
updated_at
Any advice or other options appreciated.
If you have more than 2-3 extra fields in a pivot table, its better to create an another model and make one to many relationship as you describe in option one. It will will be easy to insert and update data. But if you follow the Laravel pivot table naming convention you will get extra benefit for easy access of the data.
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I want to get Id from students table where i want insert this id in differs table . I don't really know how to explain it but maybe if you see my codes, you would understand. I have already finish making the relationship between this 2 tables already
my student controller
this my differ controller but I do not know any idea about if this code true or no
first: 'app\Differ'? but Differ is in App\Models
you can use hasOne(Differ::class); when Student model and differ in the same folder
the second thing you should know, when using functions of relationship in laravel such as hasOne, a foreign key should be named by student_id in Differ or
you show it in function like hasOne(Differ::class,'id_student','id')
I have a table customers with the fields id, name and so on.
One table doctors with the fields id, name.
Then there is one table subject_areas which has all subject areas which a doctor can have. The fields are id, text.
So, each doctor can have multiple subject areas. There is one pivot table doctor_subject which is a belongsToMany relation.
Here is my problem: A customer can have multiple doctors, but only for a specific subject area. I tried it with a new table customer_doctor with the fields id, customer_id and doctor_subject_id. But how do i map this in Eloquent?
Issue was in relation between tables. After chat clarification this came out as solution:
Html form is written in a way that customer first choose doctor, then depending on selection choose several of his available areas.
In that scenario customer needn't to be related to areas directly and should be related to areas only over relation with doctor.
Also as side note, if needed deeper relations, models on pivot tables could be created and used as well.
I have an app that houses product data via a Product model and table. Each product has specific state availability (multiple states) that I will need to filter and/or search by in the future. I am hoping to find someone who can tell me the most efficient way to store this data. As I see it, I have two options.
The first is to simply create 50 columns in my table, titled with each state name and containing a boolean value. I can then simply filter by = "avail in California" if product.ca. While this certainly works, it seems a bit cumbersome, especially when searching for multiple state availability.
The second option would be to simply have one column("states") that stores an array of available states and then filter by = "avail in California" if product.states.include? "CA". This seems like a better solution for two reasons. The first, it just allows for a cleaner DB table. Second, and more important, I can allow my user to search by simply saving the user's input as a variable(user_input) and then = "avail in California" if product.states.include? user_input. This solution does call for a little more work up front however when saving the product in the DB, since I won't be able to simply check off a boolean value.
I think option two makes the most sense, but am hoping for some advice as to why or why not. I have found a few similar questions, but they do not seem to explain which solution would be better, just how to accomplish each.
What should I do?
You should normalize unless you have a really good reason not to, and I don't see one in your overview.
To normalize, you should have the following tables:
product table, one record per product
state table, one record per state
product_state table, one entry for every product that is in a state
The product_state schema looks like this:
(product_state_id PK, product_id FK, state_id FK)
UNIQUE INDEX(product_id,state_id);
This allows you to have a product in zero or more states.
I assume that since you’re selling products, you will be charging taxes. There are different taxes by state, county, city. There are country taxes in some countries too.
So you need to abstract these entities into a common parent, usually called GeopoliticalArea, so that you can point a single foreign key (from, say, a tax rates table) at any subtype.
create table geopolitical_area (
id bigint primary key,
type text not null
);
create table country (
id bigint primary key references geopolitical_area(id),
name text not null unique
);
-- represents states/provinces:
create table region (
id bigint primary key references geopolitical_area(id),
name text not null,
country_id bigint references country(id),
unique (name, country_id)
);
insert into geopolitical_area values
(1, 'Country'),
(2, 'Region');
insert into country values
(1, 'United States of America');
insert into region values
(2, 'Alabama', 1);
I want to know how to handle mysql tables created with constraints in joomla.
for a example,
theater_table
id , name, description, image, address, tel, fax ,email
theater_facility_table
id, theater_id, facility_id
facility_table
id, name, description, image
Facility table already filled with data and id is the primary key. When creating a theater I am adding facilities to it. I created facility and theater JTables.
Do I have to create theater_facility JTable too?
Using theater Model class how I insert data to theater_facility table. I know I can insert data after theater stored successfully creating and calling storeTheaterFacility() method where it contains insert query to save required information. But I feel it can't be a good method to do so. Please help me to solve this.
Depending on how you implemented the theater - facility relationship, you can handle insering new data in different parts of your code. I mean, if for example your JTable class (the one that loads theaters) is loading/saving the theater-facilities relationship too, then the same class should delete it.
May be you can take a look at other components (for example, com_content, which relates an article to a category, or K2, where you can have multiple tags related to multiple "items"(articles)), so you can take a look on how do these components handle these kind of relationships.
Another important point you shouldn't forget is to update your facility model / table to delete records from the relationship table upon facility deleting.
I hope it helped!