I am using sqlite3 in development and mysql in production on a Rails 3.2 app.
I'd like to be able to backup the mysql, and also to create a sqlite copy of it for use in the development environment. Anyone know how to do this, or the preferred way to back up mysql at least?
I'm partial to this one, and use it to convert to/from MSSQL, sqlite and MySQL quite a lot:
https://github.com/unixmonkey/rails_db_convert_using_adapters
This may not be feasible if you have a large DB, but I am working with a rather small one (about 10MB).
(1) I back up all of my model classes into a .zip file using a rake task, and then
(2) have a button (with admin authentication) that runs another rake task to reload the data.
So I can backup the data in dev/prod mode, push my files to the other environment, and reload the data from backup (it's in .csv files, so it's DB-independent). This worked for me switching between sqlite3 and mysql2 (I am using Rails 4.0.1 if that's relevant).
I can post code if that would be helpful to people, but it's a little messy so I'll save the eyesore unless someone would find it helpful. I've found the .csv into .zip file backup to be a nice workaround for different SQL systems, if you're working on the order of megabytes.
Related
I did a homework on Rails using RubyMine.
I need to submit the homework with the database tables . But I can't access database tables file location, because I don't know under the which folder I created with migrate. I have migrated tables at the rubymine terminal
I used postgresql for database.
I will be so happy if you could help me. Thank you from now.
There is a schema.rb file that represents your database under db/ folder. So this is the answer for your first question.
The answer to second question is in order to deploy your code on a different computer, the third-party softwares need to be installed. In your scenario, this third-party is postgres as db server. To deploy your code, just type on your terminal rake db:setup. This command will create your database, run migrations and finally seed your database if db/seed.rb contains something. As a result, after rails s there should be some output.
It is worth to note that Rails is db agnostic framework. If you did not use postgres specific features then you would use mysql or sqlite on different computers/servers. But keep in mind that you should change the adapter from config/database.yml if you want to use another database.
Ödev sunumunda başarılar.
I am learning RoR using M Hartls Rails tutorial book. I am very much new to the world of databases. I created the application(simple one, just on 3rd chapter) and did my RSpec and made few static pages. I wanted to migrate from sqllite3 to postgres.
I changed the database.yml to postgres deleting the full sqlite3 specifications. Now I run my app it does not work? It says 'PG:' Error.
I need to first understand how the data is stored in sqlite? I searched the db directory and I could not find the development.rb or any database file (probably because I altered the database.yml file)
In this case, I did not enter any data as such,(it still does not work , gives me error) but generally, where does the data get stored? and since I changed the database.yml file to postgres, what will happen to the existing data?
what does rake db:migrate command do?
It would be great if someone gives a simple analogy or explanation is to how this is stored then finding a solution for this problem becomes much easier.
sqlite stores its data in files in a folder on your filesystem, using its own system of storage.
postgres will do a similar thing, but in a different folder, using a different system.
You will generally never touch these folders. You don't need to know where they are or how the dbms (database management system, eg sqlite or postgres) stores the data. All your interaction with your dbms will be done either via the terminal, or the dmbs's shell client (which you launch in the terminal aka the shell), or via a desktop client, or via your rails app's own connection with the dbms.
When you make a new rails project you need to create the database it will use. If you switch to using a different dbms then you will need to create a new database in that dbms for your app to use. Google how to do this.
If you have data in one dbms and you want to bring it into a different dbms then you will need to export it from the first dbms and import it into the second dbms. Google how to do this.
rake db:migrate will run any migrations which haven't been run in your current database (ie the one in your database.yml). Rails creates a table in your database to store which migrations have been run already: this is how it keeps track. It will fail if you haven't created the database yet.
Is storing version of Rails application in database is the right way ? Rails version it's a release production code version incremented every time we are doing deployment. It used for informational purposes only. Generally people recommended setting up version in config/initializers/version.rb but IMO it could be hard for change automatically during deployment (adding file to .gitignore or not and etc.) Using AR record we could easily had ApplicationVersion.last.to_version in our code. What do You thing about this ?
How about writing it out to a yaml file that you could generate during deployment? It'd be a simple matter to generate that during deployment, especially if you're using a tool such as capistrano.
My concern about writing it to a file is that the production database isn't a concrete resource. What if you have a crash and need to restore the database? The database potentially will report a different version than the current state of the code.
I'm completely new to Ruby on Rails, have never worked on it, but I am supposed to take over somebody else's old project. He designed a webapp that logs into a website/server online, extracts data from it daily and performs calculations. However, the application has not been running for quite some time, so now when it tries to display statistics, the page crashes. It uses data from a 5 week period and currently only has data for 2 days.
I need to manually insert data for the missing weeks in order to get it up and running again, but the problem is I don't know how to find/access its database, nor how exactly to use Ruby on Rails. I found several files in the db directory of his project, however they were mostly .sqlite33 files or just 'files'. I downloaded sqlite precompiled binary for Windows and tried to use it, but not sure what to do. I also downloaded and tried using SQTView to open the files to change the tables, but I have had no luck.
How can I tell which file is the main database and how do I edit it? And what are .sqlite33 files? Thanks.
EDIT
The application produces a
TypeError in HomeController#index
"nil can't be coerced into Float"
It links the error to a line in the code, but the only reason the error happens is because there is no data in the table for the time period that the variable in this line of code tries to use. That is why I want to manually update it with values.
I think that Sqliteman might do the trick and thank-you for explaining all of this to me. I just have to confirm it works after editing.
EDIT2
Okay, so I had a small revelation while experimenting on his app. It turned out that the page crashed because of empty values for full weeks. If I used the app to gather data for at least one day per week up until this week, then the app worked.
Is there a way I can populate all the missing days without having to manually click the days in its calendar because it takes a good 20-30 seconds for it to load?
Thank you very much for your help.
A Rails application's database is defined in config/database.yml - though the database itself and the scheme are in the db folder. In database.yml you'll find three database configurations - development, test and production - so make sure to choose the right file.
I've never heard of .sqlite33 files, but to edit SQLite files manually I recommend SQLiteMan. But I don't recommend editing it manually.
What I do recommend is to check if you are running the app in development or production mode, as the two mods use different databases. Try to run it in the other mode.
If that doesn't work, try saving a copy of the database files, and running the commands:
bundle install
bundle exec rake assets:precompile
rake db:migrate
rake db:migrate RAILS_ENV="production"
(if you're using Linux, you might want to also run the first command with sudo)
Those commands make sure all the required gems are installed, that the precompiled assets are up to date, and that the database fits the schema. If you are running that application on the same machine and with the same database as the ones the other guy was using, than those commands shouldn't be necessary, but if you have moved the application to your own machine, or used an used an outdated db file, than those commands might fix the crash.
At any rate, if you tell us what error the application is producing we might be able to provide more assistance.
This is probably a stupidly easy question for a Rails person but is causing me no end of confusion. I downloaded several open source Rails projects but am not able to run them. Usually, are you supposed to do a db:migrate before you try to run a Rails project? I thought they were supposed to just run.
I guess it depends on how the database is configured. If it's pointing to a sqlite db, then its probably all ready to go, otherwise if its a full blown RDBMS, then yes the database would need to be migrated assuming of course that the settings in database.yml are configured correctly.