I am looking for a way to map existing tables in a project with the Eloquent ORM and use them in code. I use a MySQL database and plan to migrate to MSSQL. Any way points are appreciated.
You'll have to do this manually.
i.e., create an eloquent model for each of the tables you want access to in your code using eloquent.
If you don't have timestamps named created_at and updated_at, in your model you can disable those columns.
Manually
If you have a users table you could 'map' it with a user.php file in your models folder like this
class User extends Eloquent {
protected $table = 'users';
public $timestamps = false;
}
Via artisan
You can use Jeffrey Ways Laravel Generators to help streamline the initial creation of your models, however you'll still need to make the timestamp modification manually.
This looks like an old post, but it was edited a couple of days ago, so I don't know if the original author is looking for a solution again, but if someone needs this info, here is a packagist package for Laravel 5 to do what you are asking.
Laravel 5 model generator from existing schema:
https://packagist.org/packages/ignasbernotas/laravel-model-generator
Hope that helps someone!
There is also a Eloquent Model Generator library. It can be used for generating Eloquent models using database tables as a source. Generated model will include relation methods, docblocks for magic field and relations and several additional properties.
Another here: https://github.com/Xethron/migrations-generator.
You'll only want to use these generators for local development, so you don't want to update the production providers array in config/app.php. Instead, add the provider in app/Providers/AppServiceProvider.php.
For more details look here - https://packagist.org/packages/ignasbernotas/laravel-model-generator#user-content-installation
You can also use SQL Server Migration Assistant (SSMA) to port the database to SQL Server, but you will still need to write your own models to match the schema.
http://blogs.msdn.com/b/ssma/
http://www.microsoft.com/en-us/download/details.aspx?id=43688
Still this might help get halfway there, from both sides of the puzzle.
Related
Is there a way to create database tables dynamically in Laravel. I have one Laravel build which has a database schema for quotes using the migrations tool. There will be several customers using the system which need to each have their own database table.
What I would like to happen is that when a function is called by the customer it will use the quotes schema to create a new table like 'customer1_quotes' and use this table for the customer in future. Additionally when migrations are run it will apply the updates to all tables with the given name structure (*_quotes).
If anyone has details to achieve this or a recommend alternative approach please message :)
Create a trait used by observers
Create a trait which loops through your customers and creates/updates the tables. You don't have to be in a migration to call DB::.
Use the trait in create/update controllers or better for model create/update observers. You could also create a console command for manual triggering or testing.
This should not be executed during maintenance. Using php artisan down should ensure no jobs are run during migrations.
The migrations for the customer{id}_quotes tables can loop through the available tables by querying table names using LIKE and/or REGEXP. See link below.
Links
Laravel Model Observers
How to dynamically set table name in Eloquent Model
Laravel's table Blueprint docs (5.8)
Get table names using LIKE or REGEXP
Optimization: Chunking results when getting query builder results
Edit: A repeatable migration probably won't work well and is confusing to others. Using a trait for flexibility to use for an observer is better for this.
As per the django docs when creating django migrations we should use apps.get_model() rather than importing the models and using them.
Why does a data migration have to use the historical version of a model rather than the latest one?(The historical versions of the model will not be in use anyways right?)
It uses the historical versions of the model so that it won't have problems trying to access fields that may no longer exist in the code base when you run your migrations against another database.
If you removed some field from your model and then wanted to run your migrations on some new database, and you were importing your models directly, you can expect your migrations would complain trying to use a field that doesn't exist. When using apps.get_model(...) Django will try to be smart about it and use the definitions of migrations.AddField(...) from your migrations files to give you the correct version of your model at that point in time.
This is also why Django says to be careful about using custom Model/Model Manager methods in your data migrations because I don't believe they can recreate these methods from the migrations history, or the behaviour can change over time and your migrations wouldn't be consistent.
Consider this model:
class A(models.Model):
field1 = models.PositiveIntegerField()
field2 = models.PositiveIntegerField()
Your migration history knows about these two fields and any further migration will consider this model state and will make changes to this model state.
Now suppose, you remove field1 and your model becomes:
class A(models.Model):
field2 = models.PositiveIntegerField()
And in the migration, you try to use field1, django should know that field1 existed. Hence when we use apps.get_model(), it helps django use the previous migrations history and infer about field1. Otherwise you will get an error.
I'm working with Django and I added a new model variable meaning that I need another column in my sqlite3 data base.
I have heard that I'm supposed to use sqlite> , but I am really confused when I start to use it. So, if that is part of the solution, can you be very specific on what to do?
thanks
MORE INFO:
my app is called "livestream" & and my class is "Stream"
I added the model "channel"
returns ---->
DatabaseError: table livestream_stream has no column named channel
You can ALTER TABLE to add a new column in Sqlite3 but not rename it nor drop it. Sqlite3 is a very useful database for bootstrapping your app. But sooner or later, you will need to change to a more robust/flexible database engine, say MySql or Postgresql.
Every time you add a new column to your models using Sqlite, you will need to recreate the schema (as far as I know, when you do migrations with Sqlite to add new columns, south complaints. see below). An approach I like more is use MySql with Django-South from the beginning, where I'm not sure about every aspect of my database.
Django South is an app for doing database migrations. It's very useful and the docs are a good starting point for beginners.
Every time you should make modifications to your database, you should consider them as migrations and use South.
Hope this helps!
I am writing project on ASP.NET MVC 4. The database for this project was not originally designed, and the modification or addition of new tables in the database is done campaign work. I use ADO.NET EF DatabaseFirst. During the work I needed additional properties to store information that I have ordered in the class with the fields of the database.
After that, I need to add a new table, but all of my follow-up in class with fields disappeared after the model update ADO.NET. Who knows how to safely modify my model no change of work already done?? Thanks in advance.
I am building a site that needs to display some product info from a Magento Database, but display it on another page/site outside the Magento intallation. I know the information gets displayed twice, but I would like the site to avoid content duplication and pull that same info from an only source, the Magento product database.
Is this posible? Has anyone done it?
What would be a lot easier to do would be to pull in the entire Magento engine into your external page. This [unlike the rest of Magento] is pretty easy to do.
All you have to do is the following:
// Load Up Magento Core
define('MAGENTO', realpath('/var/www/magento/'));
require_once(MAGENTO . '/app/Mage.php');
$app = Mage::app();
Now you can use any of the Magento objects/classes as if you were inside of Magento and get your attributes
$product = Mage::getModel('catalog/product')->load(1234);
$product->getSku();
$product->getYourCustomAttribute();
etc etc.
Yes, I've done it a few ways. The safest way to do this is using the webservices Magento exposes to query objects programmatically. This will insulate you from database-level changes (such as the flat product catalog, a recent addition).
Failing that (if the performance of the webservices doesn't meet your needs), you can reconstruct the catalog data from the database directly. Use the following tables (assuming you're not using the flat catalog):
eav_entity_type
eav_attribute
catalog_product_entity
catalog_product_entity_int
catalog_product_entity_varchar
catalog_product_entity_text
catalog_product_entity_decimal
catalog_product_entity_datetime
You'll want to read up on EAV models before you attempt this. Bear in mind that this is largely the topic over which people call Magento complicated.
Hope that helps!
Thanks,
Joe