From Ruby on Rails I've learned about a comfortable and very manageable way to do database migrations.
How would one handle such cases in Qt4? It does not need to be that elaborated as Rails' solution. I'd be fine with running SQL and code snippets to go up or down the version list of my data.
I googled a little bit but there seems to be no standard solution. There even seems to be no one who scratched his head before. It looks like everybody implements their own idea of how to do that.
Is there anyone interested or working on a standard solution and like to share efforts? Or maybe even has a working implementation? I'm thinking of the idea to have something similar like the information_schema table in Rails and let the application run a wizard to up- or downgrade the database (and maybe offer to do a backup/dump first), or as another option just run the migration without wizard, maybe just a handy progressbar.
QDjango may you like, it's mimic of django database ORM
Update:
Unfortunately QDjango doesn't support migrations. – #Riateche
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I have been working on developing the models for a Django app. I am working on it in my spare time. I have an issue when it comes to testing. Whenever I realize I have a mistake in my models, I have to go through the trivial but annoying process of dropping the corresponding database and then recreating it and running python manage.py syncdb. Apparently, this is because Django's syncdb cannot change the database schema. I do not fully understand what that means. Although, I know it is a pain to have to keep deleting and recreating my database every time I try and change something in my models.
Is there a better way of doing this? Is something wrong with my install? I feel like this is such a simple thing to fix that I must be doing something wrong.
No, nothing is wrong with your installation. It is a limitation of django.
There is a 3rd party app called django-south, which can be used for managing "migrations" (changes to database models). It is a very widely used app for managing database changes.
There are lots of documentation online to help you understand how south works, and how to use it.
This is a good tutorial on south
My current development environment for C# projects is Visual Studio, with a SQL Server database and using VisualSVN to connect to my SVN repository. To manage revisions of my Stored Proceduress, Views, etc I save the ALTER script to a folder watched by my SVN client so these get included in the repository.
I have checked out some (now older) posts like this one (How to keep Stored Procedures and other scripts in SVN/Other repository? and Is there a SVN plugin for SQL Server Management Studio 2005 or 2008?) and have seen a recommendation for these tools: http://www.red-gate.com/products/sql-development/sql-source-control/ and http://www.zeusedit.com/agent/ssms/ms_ssms.html .
As I infrequently work with projects doing much DB-side programming, this has never been a major bother (a dozen scripts in a folder with some naming scheme is not much to manage manually), but I have just inherited a project with a few hundred views and 1000+ Stored Procedures which have never been included in version control.
My question is:
What process do others follow for managing the versioning of their SQL Server code - is there a an accepted, clever or otherwise obvious approach I am missing here? I am leaning currently towards the purchase of one of the aforementioned tools - but am looking for advice from the community before I do this.
I realize this may result in a tool recommendation rather than a code solution but posted to SO as I think this is the appropriate crowd to ask this of.
I would recommend you go with something like the redgate tool, and treat any SQL database in the same way you'd treat your C# source code; manually keeping track of the ALTER statements will trip you up sonner or later as the number of modifications grow..can't speak for the zeus edit tool but having used the redgate one, it "just works" - and another benefit of using a tool like this is that it can manage your migration scripts so you can make a bunch of changes on your development version, then generate a single update script to update your testing database, etc,including data changes which is imho the biggest PITA to manually manage.
The other thing to consider, even if the number of changes are infrequent and you get away with manually tracking the ALTER statements, what if someone else ends up working on the same project; now you have another potential for mismanaged change scripts....
Anyway, do let us know how you get on and best of luck with it!
I’ve been maintaining a database with around 800+ db objects in it. We've always just scripted the database objects to a svn-watched folder as you describe. We have had some issues with this method, mostly with people forgetting to script new or modified objects. At the end of the day it hasn't been a huge problem for our project, but yours may be different.
We’ve looked into a couple tools, but they always assume you are starting from scratch, and we have almost 10 years of history we’d like to preserve. In the end we just end up settling back into our text-based manual solution. It's cheap and easy.
Another option you might want to look into is setting up a Visual Studio Database Project. It will script all your objects and provide some deployment options as well. My opinion was that it tired to be a little too tightly integrated for our tastes - we have a few named references to linked databases that it just wouldn't give up on.
I am currently investigating possible options of a migration framework/tool. I like the idea of ruby migrations on which the above frameworks are based.
So I am asking for your experience, opinions and maybe a comparison between them. Are you using them in production?
thanks for responses. The goal of this question was to get a feeling about which tools is used most in the developer community but it seems that migrations are not a hot topic here.
Anyway, I have decided to go with MigSharp as the codebase seem to be pretty clean and it is quite easy to handle and had build in support for MS SQL CE. Second runner up would have been FluentMigrator where I was not able to produce a working example for compact edition.
Cheers
I use FluentMigrator in production, and am a longtime contributor to FM. I think your question is to general; be more specific. Also, FM has a google group which is fairly active if you want FM information.
FM is derived from migrator.net, as I recall. It uses a fluent-syntax, and supports multiple databases. We have taken some inspiration from rails migrations, but it's definitely not a port. Worth checking out.
One thing I've learned is not to put your migrations in the same assembly as you app code. Separate them into a migration assembly, and use that for migrating your databases.
Also, you should always work on multiple environments to avoid problems with migrations run straight against production. I always have at least a development and production environment, and most of the time there is a testing environment as well.
I use mig#.
It works well, but you will need to have some guidelines for usage - as migrations can get complicated.
We use sequence number on the end of our migrations rather than a date-time stamp. This is because we don't know when the date time stamp was set (when they begun the source code change-set; just before committing; some time inbetween) different developers could use different approaches.
Names such as Migration_0000034.cs give you plenty of space.
At this point, I would stick with migrator.net. I like the promise of FluentMigrator, but it seems to not have any better active development than migrator.net (see the issues and pull requests that have languished on their github site).
There is also no easy way to do an ExecuteScalar(). I'd add it, but I don't want to create my own fork, and I see no reason that a pull request would actually land in the master. (Execute.WithConnection is an Action so it will fire on demand rather than when I need it to fire)
So for me, I'm heading back to migrator.net.
I guess Selenium isn't that important to this question but I thought I'd add it in. Also, I'm not using Rails.
I need to access Sqlserver and delete some records using ruby. Nothing too crazy. I've found some information online but I would like to know what you recommend is the best way to do this.
I've come across the DBI and SEQUEL gems but am unsure about the amount of time I'll need to invest to get up and running. Also, are there any better alternatives?
Thank you
You might want to try tiny_tds to see if that fits your needs. It's pretty bare-bones without an ORM.
I'm in the process of starting up a web site project. My plan is to roll out the site in a somewhat rudimentary form first and then add to the site functionality along the way.
I'm using Subsonic 3 for my DAL, and I'm expecting the database will go through multiple versions as the sites evolve. This means I'll need some kind of versioning and migration tools. I understand that Subsonic has built in migration possibilities, but I'm having difficulties grasping how to use these tools, in my scenario.
First there's the SimpleRepository model, where the Subsonic "automagically" handles the migrations as i develop my site. I can see how this works on my dev-machine, but I'm not sure how to handle deployments with this.
Would Subsonic run the necessary migrations on my live site as the appropriate methods are called?
Is there some way I can force all necessary migrations on a site while taking the site offline, when using the Simplerepository model? (Else I would expect random users to experience severe performance cuts, as the migration routines kick in)
Would I be better off using the ActiveRecord model, and then handling migrations with the Subsonic.Schema.Migrator? (I suspect so)
Do you know of any good resources explaining how to handle this situation with the migrator? (I read the doc, but I can't piece together how I would use this in practice)
Thanks for listening/replying.
Regards
Jesper Hauge
I would advise against ever running migrations against a live site. SubSonic's migrations are really there to make development simpler and should never be used against a live environment. To be honest even using SubSonic.Schema.Migrator you're still going to bump into the fact that refactoring databases is an incredibly hard problem. For example renaming a column in a table using management studio is trivial, but what happens in the background involves creating an entirely new table and migrating all the constraints, data etc. before renaming the new table.
The most effective way I've found for dealing with this is:
Script all database changes as you make them in your development environment (SQL Server Management Studio will do this for you) and add these scripts to your source control.
As part of deployment (obviously backup first) run the migration scripts and then deploy the updated application on success.
Whether you use ActiveRecord or SimpleRepository is then down to whether you want the extra features/complexity of ActiveRecord.
Hope this helps
i would use activerecord easy to use and any changes you just run the TT files, you would then just build or publish your slution and done ???? SVN will keep your multiple versions of the build stage so if you make a tit of it you just drop back a revision.