I use orphan Removal to remove entities that are orphaned but I could not find a way to remove entities that never had a parent.
For example, I build a house that has rooms, I delete the house, and orphan Removal will delete the room entities, all works good.
Second scenery, I build a room first, and save it to use it in building the house later. I never used it, I did not build the house and orphan Removal will not delete this entity for me.
What can I do to remove this kind of entities on a regular basis?
I searched the internet for solutions but could not find any. I'm new to programming so I was thinking that maybe I don't search for the right thing. Any directions or tips would be amazing. Thank you
You could simply build a script that you execute everyday using cronjob on your server. If you use symfony, use console command as script to execute.
This script would retrieve orphan from database en delete it.
In local, just execute the command.
Related
I have a cloudant database with a lot of deleted docs. Since they can't be destroyed, I would like to make a filtered copy with the non deleted items to a temporary base, destroy the original one, and copy the temporary base to a fresh database with the same name as before.
The problem is when I destroy the base, the API keys generated are also destroyed...
So the front app calling the new base can't acces it !
I would like to manually create a user/password, so I can recreate the same user each time I destroy the database.
I don't know how to do it ?
Or is there another way to achieve my goal ??
To answer your actual question, you can't add "users" to a Cloudant account, only databases. You can, however, make API-keys that span multiple databases, which sounds like it could be what you want:
https://dx13.co.uk/articles/2016/04/11/using-a-cloudant-api-key-with-multiple-cloudant-databases-and-accounts/
But as was noted by bessbd above, if your data model relies on document deletion, you're working against the grain of Cloudant, and sooner or later you'll end up with problems.
And finally -- the doc links appear to work just fine.
Maybe some useful stuff here: https://blog.cloudant.com/2019/11/21/Best-and-Worst-Practices.html
[disclaimer, I wrote that]
Can you please expand a little further on your use case? Why do you want to get rid of the deleted docs? Is there a way to avoid deleting the docs? Also, have you already read https://cloud.ibm.com/docs/services/Cloudant?topic=cloudant-documents#tombstone-documents ?
I am developing a django project which lives on Heroku. As the project evolves, a problem occurs when new fields are added to a data model: during makemigration, south will ask something like the following:
...
? 1. Quit now, and add a default to the field in models.py
? 2. Specify a one-off value to use for existing columns now
...
It isn't easy get around this (I tried to choose the second answer but south wouldn't accept whatever I entered).
Questions:
1) Some suggest that null=True should be added to the new field to avoid such a problem. However, the field should not be null. I end up making a workaround: makemigration with null=True, delete null=True, perform makemigration again, and then push to Heroku.
Is this the right way of doing it?
2) Using south migration causes another problem. Because we are a development team, every member may perform migration in his/her environment. When it comes to pushing to GitHub, the 00*_* files in each app's migration folder may conflict each other. How to solve it? Currently, we just ignore the 00*_* files since our project is not in production yet. What if it is in production later?
3) I only ran makemigrations and migrate and never used schemamigration. The system runs fine though. Do I have to run schemamigration?
1)
When you get an error message like that, basically it's asking for a one-off default. What exactly you should put in there when selecting option 2 depends entirely on your situation, but it must be a valid Python expression. For example:
If I have an IntegerField I want to add, I could enter 0
For a CharField, I could use "my string" (Note the quotes must be there)
For a ForeignKey, I would specify the primary key of the object I want to use.
2)
This is the hardest part about South. Conflicting migrations have to be merged carefully, and manually. The Django 1.7 migrations that replace South are much better at doing this automatically, so if at all possible, upgrade to 1.7+.
3)
I believe makemigrations is an alias for schemamigration. Get used to makemigrations because it's what the command is called in Django 1.7+.
I'm using MigratorDotNet to manage Rails-style migrations for my web app. I have a workflow where, if I delete all the tables in the database, I can access an installation view that will run MigratorDotNet and create all the necessary tables.
This works locally. For some reason, when I upload my code to my Arvixe hosting, the migrations just never run. I get this odd error:
There is already an object named 'SchemaInfo' in the database.
This is odd because, prior to running migrations, I manually deleted all the tables in the database (to make sure it wasn't left over from a previous install).
My code essentially boils down to:
new Migrator.Migrator("SqlServer", connectionString.ToString(), migrationsAssembly).MigrateToLastVersion();
I've already verified by logging that the connection string is correct (production/hosting settings), and the assembly is correctly loaded (name and version).
Works locally, but not on Arvixe. How do I troubleshoot this?
This is a dark day.
It turns out (oddly) that the root cause was my hosting company used a schema other than dbo for my database. Because of this, the error message I saw (SchemaInfo already exists) was talking about their table.
My solution, unfortunately, was to rip out MigratorDotNet and go with FluentMigator instead. not only did this solve the problem, but it also gave me a more intelligible error message (one referring to the schema names).
While it doesn't seem possible to auto-set the schema, and while I need to switch the schema on my dev vs. production machine, it's still a solvable problem (and a better API, IMO). I googled, but did not find any way to change the default schema in migratordotnet.
I'm sorry for the issues that you were having. On shared hosting, unfortunately the only way that we may be able to change the schema is manually. If you are still looking for a solution that requires our assistance, please forward your ticket ID to qa .at. arvixe.com as well as arvand .at. arvixe.com and we can look into the best way to resolve this.
I have the following scenario:
I'm starting development of a long project (around 6 months) and I need to have some information on the database in order to test my features. The problem is that right now, I don't have the forms to insert this information (I will in the future) but I need the information loaded on the DB, what's the best way to handle this? Specially considering that once the app is complete, I won't need this process anymore.
As an example, lets say I have tasks that need to be categorized. I've begun working on the tasks, but I need to have some categories loaded on my db already.
I'm working with Rails 3.1 btw.
Thanks in advance!
Edit
About seeds:I've been told that seeds are not the way to go if your data may vary a bit, since you'd have to delete all information and reinsert it again. Say.. I want to change or add categories, then I'd have to edit the seeds.rb file, do my modifications and then delete and reload all data...., is there another way? Or are seeds the defenitely best way to solve this problem?
So it sounds like you'll possibly be adding, changing, or deleting data along the way that will be intermingled amongst other data. So seeds.rb is out. What you need to use are migrations. That way you can search for and identify the data you want to change through a sequential process, which migrations are exactly designed for. Otherwise I think your best bet is to change the data manually through the rails console.
EDIT: A good example would be as follows.
You're using Capistrano to handle your deployment. You want to add a new Category, Toys, to your system. In a migration file then you would add Category.create(:name => "Toys") or something similar in your migration function (I forget what they call it now in Rails 3.1, I know there's only a single method though), run rake db:migrate locally, test your changes, commit them, then if it's acceptable deploy it using cap:deploy and that will run the new migration against your production database, insert the new category, and make it available for use in the deployed application.
That example aside, it really depends on your workflow. If you think that adding new data via migrations won't hose your application, then go for it. I will say that DHH (David Heinemeier Hansson) is not a fan of it, as he uses it strictly for changing the structure of the database over time. If you didn't know DHH is the creator of Rails.
EDIT 2:
A thought I just had, which would let you skip the notion of using migrations if you weren't comfortable with it. You could 100% rely on your db/seeds.rb file. When you think of "seeds.rb" you think of creating information, but this doesn't necessarily have to be the case. Rather than just blindly creating data, you can check to see if the pertinent data already exists, and if it does then modify and save it, but if it doesn't exist then just create a new record plain and simple.
db/seeds.rb
toys = Category.find_by_name("Toys")
if toys then
toys.name = "More Toys"
toys.save
else
Category.create(:name => "More Toys")
end
Run rake db:seeds and that code will run. You just need to consistently update the seeds.rb file every time you change your data, so that 1) it's searching for the right data value and 2) it's updating the correct attributes.
In the end there's no right or wrong way to do this, it's just whatever works for you and your workflow.
The place to load development data is db/seeds.rb. Since you can write arbitrary Ruby code there, you can even load your dev data from external files, for instance.
there is a file called db/seeds.rb
you can instantiate records using it
user1=User.create(:email=>"user#test.com",
:first_name=>"user",
:last_name=>"name",
:bio=>"User bio...",
:website=>"http://www.website.com",
:occupation=>"WebDeveloper",
:password=>"changeme",
:password_confirmation=>"changeme",
:avatar => File.open(File.join(Rails.root, '/app/assets/images/profiles/image.png'))
)
user2=User.create(:email=>"user2#test.com",
:first_name=>"user2",
:last_name=>"name2",
:bio=>"User2 bio...",
:website=>"http://www.website.com",
:occupation=>"WebDeveloper",
:password=>"changeme",
:password_confirmation=>"changeme",
:avatar => File.open(File.join(Rails.root, '/app/assets/images/profiles/image.png'))
)
Just run rake db:seed from command line to get it into the db
I made a bad decision as I was designing a MongoDB database to embed a model rather than reference it in an associated model. Now I need to make the embedded model a referenced model, but there is already a healthy amount of data in the database (or document?).
I'm using Mongoid, so I reasoned I can just change embedded_in to referenced_in. Before I start, I figured I'd ask people who know better than I do. How can I transition the embedded data already in the database to the document for the associated model.
class Building
embeds_many :landlords
..
end
class Landlord
embedded_in :building
...
end
Short answer - Incrementally.
Create a copy of Landlord, name it Landlord2.
Make it referenced in Building.
Copy all data from Landlord to Landlord2.
Delete Landlord.
Rename Landlord2 to Landlord.
Users should not be able to CRUD Landlord during steps 3-5 (ideally). You still can get away with only locking CRUD on 4-5. Just make sure you make all updates that happened during copying, before removing Landlords.
Just chan ging the model like you have above will not work, the old data will still be in a different strucutre in the db.
Very similar the previous answer, one of the things I have done to do this migration before is to do it dynamically, while the system is running and being used by the users.
I had the data layer separated from the logic, so it let me add some preprocessors and inject code to do the following.
Lets say we start with the old datamodel, then release new code that does the following:
On every access to the document, you would have to check whether the embedded property exists, if it does, create a new entry associated as a reference and save to the database and delete the embedded property from the documents. Once this is done for a couple of days, a lot of my data got migrated and then I just had to run a similar script for everything that was not touched, made the job of migrating the data much easier and simpler and I did not have to run long running scripts or get the system offline to perform the conversion.
You may not ha ve that requirement, so Pick accordingly.