Adding new columns to an Existing Doctrine Model - codeigniter

First of all Hats of to StackOverflow for their great service and to you guys for taking your time to answer our questions.
I am using Doctrine ORM 1.2.4 with CodeIgniter 1.7.3. I created a Site with some required tables and pumped in with datas only to realize at a later point of time that a specific table needs to have one more column.
The way i created the tables was by writing the model as php classes which extend the Doctrine_Record.
Now i am wondering if i need to just add the column in the model that requires a new column in the setTableDefinition() method and recreate that table or is there any other way that easily does this. The former method i've mentioned requires me to drop the current table along with the datas and recreate the table which i do not wish. Since doctrine seems to be a very well architect-ed database framework, i believe it is lack of my knowledge but surely should exist a way to add new columns easily.
PS: I am not trying to alter a column with relations to other tables, but just add a new column which is not related to any other table. Also i create the tables in the database using Doctrine::createTablesFromModels(); When i alter a table with a new column and run this method it shows errors.

Since you don't want to drop & recreate, use a Doctrine Migration.
The official docs here show many examples:
http://www.doctrine-project.org/projects/orm/1.2/docs/manual/migrations/en
Since you just want to add a field, look at their second code example as being the most relevant which is like this:
// migrations/2_add_column.php
class AddColumn extends Doctrine_Migration_Base
{
public function up()
{
$this->addColumn('migration_test', 'field2', 'string');
}
public function down()
{
$this->removeColumn('migration_test', 'field2');
}
}

Related

Can this block of code of mine can be improved

[This is to populate data from two tables that one has two foreign keys from the same column as reference on the other table]
https://i.stack.imgur.com/D8fiv.png
[This is my schema for the table with the foreign key]
https://i.stack.imgur.com/eYDL0.png
This is written in laravel and it is working however i have an itchy feeling that this is wrong
As someone else has commented, you should put the code in your question. More context might also be necessary as it's not clear what you are trying to return from your view(). Are you returning $citizen, $family, or both? It would also be helpful to include what version of Laravel you are using. I'll assume you are using the latest Laravel 8.
Your code should work but you are making more work for yourself if you don't utilize Laravel's relationships. If you do, all the query stuff you have in your code can be reduced to just a few short lines of code such as this:
public function view(Citizen $citizen)
{
$citizen->load('family');
return $citizen;
}
Database Migration
You can shorten your migration by using foreignId(). See docs for details
https://laravel.com/docs/8.x/migrations#foreign-key-constraints
Before:
$table->integer('client_id')->unsigned();
$table->foreign('client_id')->references('id')->on('citizens');
After:
$table->foreignId('client_id')->constrained();
Route Model Binding
I'm assuming your view() method is in your controller and is called from a route. Since the one parameter required is the client's id, you can use Route Model Binding and skip fetching the client from the database.
https://laravel.com/docs/8.x/routing#route-model-binding
public function view(Citizen $citizen)
{
// your code
}
Relationships
You seem to have relationships set up but you aren't using them to load data. You should be able to load the related objects without any manual queries.
If you have a belongsTo(One to Many) relationship on the Citizen model to the Family model, you can load it like this:
$citizen->load('family');
or just use it like this
$relationship = $citizen->family->relationship;
I don't know what the relationships between your models are but you should read up on the different relationship types in the docs.
https://laravel.com/docs/8.x/eloquent-relationships

Laravel Dynamic Eager Loading for Dynamic Relationships

Laravel Version: 5.5
PHP Version: 7+
Database Driver & Version: mysql 5.7+
Scenario:
I have a SaaS application that has flexible database structure, so its fields are bound to change, especially given it has a Json field (for any extra database structure to be created from client side of the application), including relationship based fields. so Account Table can have dynamically created employee_id field, and thus the need to access relationships dynamically
Problem:
I need to EagerLoad models based on this dynamic relationship. If I had something like this:
// Account Model
public function employee(){
return $this->belongsTo(App\Employee);
}
it would be easy. But what I have is this:
public function modelBelongsTo(){
return $this->belongsTo($dynamicClassName, $dynamicForeignKey);
}
Now if I eager load this, I'll get Account Model instance with related Employee on key modelBelongsTo. This is how Eloquent Names based on the function of eagerload. But after this I cannot use this function again to eagerload a second model because it'll just overwrite results on modelBelongsTo key.
Possible Solution Directions:
1) Can I Somehow change laravel's process to use a name I provide?
or
2) Can I write functions on the fly to overcome this so I'll write employee function on the fly?
or
3) Worst Case Scenario: I iterate over all records to rename their keys individually because I am using a pagination, it wouldn't that big of a deal to loop over 10 records.
Us a morph relationship
define the various dynamic classnames say
Employee
Boss
Morph works by having the related key and the table name stored in the parent table, it means to relate them you have to use a join or an orm and you cant have foreign key constraint on it as it links to different tables.
then have your account have morphs where
we have
Account
as top class
then we have
EmployeeAccount, BossAccount
which have their relation to boss and employee
then in Account have morphto relation call it specificAccount()
to which in its child morphs have the morph relation to Account
then add it to $with so to eager load them so when fetching account you could simply do
$account ->specificAccount
to get its morph child. which is nullable
This is totally dynamic such that if you have other classes in future you can just add and add the morph relationship. This may be applied to any reflection or runtime evaluated and loaded classes/code though it is not advisable to do this, as you can always edit code to create new functionality without affecting previous.

Laravel Database migrations Schema builder custom column type

I am trying to create migrations with Laravel but I am in a situation where I need custom column type since the one I want isn't included in schema builder , which is "POLYGON". So I want to know, how I can create my custom column type, other than those that are already in the Schema builder.
What I want would look like this in SQL statement:
alter table xxx add polygon POLYGON not null
Is it possible to do it by myself or I am forced to use some library like this?
I know that I can do like this:
DB::statement('ALTER TABLE country ADD COLUMN polygon POLYGON');
but it leads me to the error that the table doesn't exist.
There is no built in way to do this but you can achieve a good result with minimal code.
<?php
use Illuminate\Database\Schema\Grammars\Grammar;
// Put this in a service provider's register function.
Grammar::macro('typePolygon', function (Fluent $column) {
return 'POLYGON';
});
// This belongs in a migration.
Schema::create('my_table', function (Blueprint $table) {
$table->bigIncrements('id');
$table->addColumn('polygon', 'my_foo');
});
The key is to add a function with the name typePolygon to the Grammar class because this function is what determines the actual type used by the particular DBMS. We achieve this by adding a macro to the Grammar.
I have written a blog post about how to extend this solution to any custom type: https://hbgl.dev/add-columns-with-custom-types-in-laravel-migrations/
I assume you require spatial fields in your DB... I would consider via Packagist.org and search for laravel-geo (or equivalent) - which supports spatial column tyes inc Polygon. You could then use standard Laravel migration files for your custom fields -e.g.
$table->polygon('column_name');
In your UP function in your migration file...

Update Schema via an Eloquent Model, Laravel 5.2

i'd like to know if it's possible at all to update the table schema in a Migration through a specific Eloquent Model, or if i actually need to pass in the name of the Table and Connection every single time.
I ask this because in my case this requires an additional configuration file that my package must publish to the end users, apart from the already required table Eloquent model (which is used for other purposes)
You can update schema later and add or drop columns and/or index.
To do this you create a new migration and add the changes there. It will change the table over your previous version.
More info in Laravel documentation.
For renaming the table
Schema::rename($from, $to);
https://laravel.com/docs/5.2/migrations#renaming-and-dropping-tables

Laravel5: How are Eloquent model relationships expressed in the database?

There's a missing link I fail to understand.
I use migrations to create database tables and I define the relationships there. meaning.. if I have a person table and a job table and I need a one to many relationship between the person and jobs, I'd have the job table contain a "person_id".
When I seed data or add it in my app, I do all the work of adding the records setting the *_id = values etc.
but somehow I feel Laravel has a better way of doing this.
if I define that one to many relationship with the oneToMany Laravel Eloquent suports:
in my Person model.....
public function jobs()
{
return $this->hasMany('Jobs);
}
what's done on the database level? how do I create the migration for such table? Is Laravel automagically doing the "expected" thing here? like looking for a Jobs table, and having a "person_id" there?
Yep, Laravel is doing what you guess in your last paragraph.
From the Laravel documentation for Eloquent Relationships (with the relevant paragraph in bold):
For example, a User model might have one Phone. We can define this
relation in Eloquent:
class User extends Model {
public function phone()
{
return $this->hasOne('App\Phone');
}
}
The first argument passed to the hasOne method is the name of the
related model. Once the relationship is defined, we may retrieve it
using Eloquent's dynamic properties:
$phone = User::find(1)->phone;
The SQL performed by this statement
will be as follows:
select * from users where id = 1
select * from phones where user_id = 1
Take note that Eloquent assumes the foreign key of the relationship based on the model name. In this case, Phone model is assumed to use a user_id foreign key.
Also note that you don't actually have to explicitly set the foreign key indexes in your database (just having those "foreign key" columns with the same data type as the parent key columns is enough for Laravel to accept the relationship), although you should probably have those indexes for the sake of database integrity.
There is indeed support to create foreign key relationships inside migration blueprints and it's very simple too.
Here is a simple example migration where we define a jobs table that has a user_id column that references the id column on users table.
Schema::create('jobs', function($table)
{
$table->increments('id');
$table->integer('user_id')->unsigned();
$table->foreign('user_id')->references('id')->on('users');
});
You can also use some other methods that laravel provides such as onDelete() or onUpdate
Of course to understand better the options that are available to you please read the documentation here.
Edit:
Keep in mind that Eloquent is just using fluent SQL wrapper and behind the scenes there are just raw sql queries, nothing magical is happening, fluent just makes your life a lot easier and helpers you write maintainable code.
Take a look here about the Query Builder and how it works and also, as #Martin Charchar stated , here about Eloquent and relationships.

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