My company has a handful of apps that we deploy in the websites we build. Recently a very old app needed to be included along side a newer app and there was a conflict w/ a duplicate table name needed to be used by both apps.
We are now in the process of updating an old app and there will be some DB updates. I'm curious what people consider best practice (or how do you do it) to help ensure these name collisions don't happen.
I've looked at schema's but not sure if thats the right path we want to take. As the documentation prescribes, I don't want to "wire" a particular schema name into an application and if I add schema's to the user search path how would it know which table I was referring to if two schema's have the same table name. although, maybe I'm reading to much into this.
Any insights or words of wisdom would be greatly appreciated!
Postgres has namespaces which is definately the most efficient way of handling that sort of thing :)
Just create a new namespace for the old database and you're done. The way most PHP/MySQL solutions solve it (specific prefix per app) is also an option, but not one I'd recommend.
[edit]Specifically, you can call your tables like this the_namespace.tablename besides changing the search_path. For the rest, the search_path will decide your namespace if you don't add the namespace.
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I was working on a project which is already advanced, specially the database, that has been filled by someone from my team, even though part of it has not been used yet. Some tables can be emptied and refilled as it's sample data, however most of them contains data which will be actually used or it's been used in the parts we're doing now.
The project started in CodeIgniter, by we've realized that Laravel can save us hours of work, so we're planning to migrate it. The point is that we didn't use the CodeIgniter's migration system, and we've seen in the Laravel documentation that only the table structure will be migrated, plus we have to create every migration.
The question here is if there's a way to both, create the migratinos files automatically, and to keep the relevant data that will be used in the application so we don't need to refill the database again (yep, there are kind of big tables). We thought on the seeders, but what we've seen is that they only store sample data...
You can use Laravel migration generator. It will simply help you to generate migrations from your
existing database. Check it out below. You will find in readme how to use it. Good luck.
https://github.com/Xethron/migrations-generator
Hope , it helps. Thanks. Cheers. -_-
We are encountering strange hibernate behavior with hbm2ddl.auto set to update.
In our test setup, we have two database users, one containing the tables for our beta application, the other one is mainly used for development. I.e. same table names with different users.
When new tables are to be created, we do so by using hbm2ddl.auto=update.
Now suddenly the strange behavior is: the update process looks for existing tables with the wrong user and creates those not found with the right user.
E.g. if the following tables exists
USER_A.TABLE_1
USER_B.TABLE_2
and we update with three tables configured: TABLE_1, TABLE_2, TABLE_3 using USER_B, we end up with
USER_A.TABLE_1
USER_B.TABLE_2
USER_B.TABLE_3
TABLE_1 is not created for USER_B. After renaming USER_A.TABLE_1 to USER_A.TABLE_0 and updating again we end up with the expected result:
USER_A.TABLE_0
USER_B.TABLE_1
USER_B.TABLE_2
USER_B.TABLE_3
Does this make any sense to anyone? Is there something like an internal hibernate cache remembering like "Hey I have already created this table on this server (and I do not care about the user)".
We have spent quite some testing to reassure this is not a configuration problem, reproduced this on different machines, different configurations, from ant or using the IDE, making sure USER_A's password cannot be found anywhere in the build directory etc. So we are 100% sure, the behavior is as described - but we are completely out of ideas what happens.
I'd be very happy to hear your ideas about this, since this problem is nagging for some time now.
Thanks a lot,
Peter
Is there something like an internal hibernate cache remembering like "Hey I have already created this table on this server (and I do not care about the user)".
No. What is probably happening is that USER_A can see the tables created under USER_B account, and vice-versa. It's not clear which database you are using, but I would try to configure Hibernate to use two different schemas, in addition to use just different users. You may also want to try to set the property "hibernate.default_schema", but I'm not sure that this only will solve your problem.
We currently use an SVN repository to ensure everyone's local environments are kept up-to-date. However, Drupal website development is somewhat trickier in that any custom code you write (for instance, PHP code written for a node body) is stored in the DB and the changes aren't recognized by the SVN working copy.
There are a couple of developers who are presently working on the same area of a Drupal site, but we're uncertain about how to best merge our local Drupal database changes together. Committing patches of database dumps seem clumsy at best and is most likely inefficient and error-prone for this purpose.
Any suggestions about how to approach this issue is appreciated!
Unfortunately, database deployment/update is one of Drupals weak spots. See this question & answers as well as this one for some suggestions on how to deal with it.
As for CCK, you could find some hints here.
As for php code in content, I agree with googletorp in that you should avoid doing this. However, if for some reason you absolutely have to do it, you could try to reduce the code to a simple function call. Thus you'd have the function itself in a module (and this would be tracked via SVN). But then you are only a little step from removing the need for the inline code anyways ...
If you are putting php code into your database then you are doing it wrong. Some stuff are inside the database like views and cck fields plus some settings. But if you put php code inside the node body you are creating a big code maintenance problem. You should really use the API and hooks instead. Create modules instead of ugly hacks with eval etc.
All that has been said above is true and good advice.. To answer your practical question, there are a number of recent modules that you could use to transport the changes done by the various developers.
The "Features" modules is a cure the the described issue of Drupal often providing nice features, albeit storing lots of configs and structure in the DB. This module enables you to capture a feature and output it as a pseudo-module (qualifies as a module with .info and code-files and all). Here is how it works:
Select functionality/feature to export
The module analyses the modules, files, DB content that is required to rebuild that feature elsewhere
The module creates a pseudo-module that contains the instructions in #3 and outputs everything (even SQL to rebuild the stuff in the DB) into a module package (as well as sets dependencies for other modules required)
Install the pseudo-module on your new site and enable it
The pseudo-module replicates the feature you exported rebuilding DB data and all
And you can tell your boss you did it all manually with razor focus to avoid even 1 error ;)
I hope this helps - http://drupal.org/project/features
By committing patches of database dumps, do you mean taking an entire extract of the db and committing it after each change?
How about a master copy of the database? Extract all tables, views, sps, etc... into individual files, put them into svn and do your merge edits on the individual objects?
Are there tools that make the job easier? If command-line only tools exist, then can anyone speculate if there is a market for a GUI tool? For example, you can create a relational database by modeling visually. Should the same notion exist for LDAP?
Apache Directory Studio includes an ldif-Editor. It is still a text editor but with syntax highlighting, autocompletion and group collapsing for ldif files:
http://directory.apache.org/studio/
I don't know if there are any tools but it isn't that hard to create them by hand.
If you are using IPlanet LDAP then they had a nice interface for creating and modifying schemas though. :)
I don't know if you would consider that to be by hand otherwise that is one tool to use.
I've done some LDIF handling using Perl and the Net::LDAP::LDIF module and it made scripting custom LDAP conversions very easy.
Have you looked at the command-line tool, LDIFDE.exe? Should be on your domain controller.
Business people give me Excel spreadsheets with inconsistent formatting of user and group data and want it loaded right away (then they come back with a new version and tell me they've only added some new users, but some are missing, some data is now invalid, there's a missing column etc.) They want unique passwords assigned, group memberships set up based on department id fields, and so forth.
Then they come back two weeks later and want to know about the differences between that spreadsheet and one from six months ago. Sigh.
I generally just do it all with a few hand-crafted Python scripts.
A lot of times you may be copying objects from one tree to another. Or backing them up. In that case, most LDAP tools have some way of exporting as LDIF. Then you can easily modify the files as needed.
Or copy examples to reuse.
I have seen a number of tools that will do tasks and output the results as LDIF, which can be handy, but they are basically point usage tools.
I'm work on project with django framework and use control version system to synchronize my code with other peoples. But i don't know how organize work with database.
In django, any people, worked on project, may changes django models, and tell 'syncdb' to synchronize model objects with db.
But other people don't about this changes, and it's code revision may not works.
Please, tell me some ways to solve this problem (maybe, different db or something another).
Thanks, and excuse my english :)
You have to actually talk to the people on your project.
If someone changes any database model, they have to actually tell everyone else about the change. This is not a Django problem.
Think of any SQL database -- without Django. When the DBA drop's a table, they have to tell everyone that they changed the database. Otherwise all programs that use the table break.
The model definition is special, and whoever can change this must tell everyone else.
You must have an initial backup of the DB under verison control. And after that you have to put all the modification scripts on the same version control. Something like this:
/Database (in the repository)
Initial backup
Script1_date.sql
Script2_date.sql
...
I'm not sure to understand your problem; but remember that on Django, syncdb only creates new tables. It doesn't alter an existing table.
If, for example you just add a new field, a syncdb won't do anything.
Actually, looking at the alternatives, I'm often surprised that nobody mentions South
http://south.aeracode.org/
It seems to be the best migration app out there... perhaps I am missing something important, but I find it pretty nice to work with...
take also a look at deltasql.
you can test it at http://www.gpu-grid.net/deltasql (username: admin password: testdbsync )
and download from http://sourceforge.net/projects/deltasql
ciao :-)
I'm curious...what happens if you put your MDF and LDF files under source control? Of course if your tables are empty and you just have the structure of the database...
Sounds like you want migrations.
As an example:
http://www.aswmc.com/dbmigration/
You may also want to add functional unit tests that actually test that the schema is as expected, that way when the tests fail, you can see that it is a schema change, and audit whether it will affect other parts of the app. If it doesn't, fix your test to take into account the new schema.