Is there a version control system for database structure changes? - sql

I often run into the following problem.
I work on some changes to a project that require new tables or columns in the database. I make the database modifications and continue my work. Usually, I remember to write down the changes so that they can be replicated on the live system. However, I don't always remember what I've changed and I don't always remember to write it down.
So, I make a push to the live system and get a big, obvious error that there is no NewColumnX, ugh.
Regardless of the fact that this may not be the best practice for this situation, is there a version control system for databases? I don't care about the specific database technology. I just want to know if one exists. If it happens to work with MS SQL Server, then great.

In Ruby on Rails, there's a concept of a migration -- a quick script to change the database.
You generate a migration file, which has rules to increase the db version (such as adding a column) and rules to downgrade the version (such as removing a column). Each migration is numbered, and a table keeps track of your current db version.
To migrate up, you run a command called "db:migrate" which looks at your version and applies the needed scripts. You can migrate down in a similar way.
The migration scripts themselves are kept in a version control system -- whenever you change the database you check in a new script, and any developer can apply it to bring their local db to the latest version.

I'm a bit old-school, in that I use source files for creating the database. There are actually 2 files - project-database.sql and project-updates.sql - the first for the schema and persistant data, and the second for modifications. Of course, both are under source control.
When the database changes, I first update the main schema in project-database.sql, then copy the relevant info to the project-updates.sql, for instance ALTER TABLE statements.
I can then apply the updates to the development database, test, iterate until done well.
Then, check in files, test again, and apply to production.
Also, I usually have a table in the db - Config - such as:
SQL
CREATE TABLE Config
(
cfg_tag VARCHAR(50),
cfg_value VARCHAR(100)
);
INSERT INTO Config(cfg_tag, cfg_value) VALUES
( 'db_version', '$Revision: $'),
( 'db_revision', '$Revision: $');
Then, I add the following to the update section:
UPDATE Config SET cfg_value='$Revision: $' WHERE cfg_tag='db_revision';
The db_version only gets changed when the database is recreated, and the db_revision gives me an indication how far the db is off the baseline.
I could keep the updates in their own separate files, but I chose to mash them all together and use cut&paste to extract relevant sections. A bit more housekeeping is in order, i.e., remove ':' from $Revision 1.1 $ to freeze them.

MyBatis (formerly iBatis) has a schema migration, tool for use on the command line. It is written in java though can be used with any project.
To achieve a good database change management practice, we need to identify a few key goals.
Thus, the MyBatis Schema Migration System (or MyBatis Migrations for short) seeks to:
Work with any database, new or existing
Leverage the source control system (e.g. Subversion)
Enable concurrent developers or teams to work independently
Allow conflicts very visible and easily manageable
Allow for forward and backward migration (evolve, devolve respectively)
Make the current status of the database easily accessible and comprehensible
Enable migrations despite access privileges or bureaucracy
Work with any methodology
Encourages good, consistent practices

Redgate has a product called SQL Source Control. It integrates with TFS, SVN, SourceGear Vault, Vault Pro, Mercurial, Perforce, and Git.

I highly recommend SQL delta. I just use it to generate the diff scripts when i'm done coding my feature and check those scripts into my source control tool (Mercurial :))
They have both an SQL server & Oracle version.

I wonder that no one mentioned the open source tool liquibase which is Java based and should work for nearly every database which supports jdbc. Compared to rails it uses xml instead ruby to perform the schema changes. Although I dislike xml for domain specific languages the very cool advantage of xml is that liquibase knows how to roll back certain operations like
<createTable tableName="USER">
<column name="firstname" type="varchar(255)"/>
</createTable>
So you don't need to handle this of your own
Pure sql statements or data imports are also supported.

Most database engines should support dumping your database into a file. I know MySQL does, anyway. This will just be a text file, so you could submit that to Subversion, or whatever you use. It'd be easy to run a diff on the files too.

If you're using SQL Server it would be hard to beat Data Dude (aka the Database Edition of Visual Studio). Once you get the hang of it, doing a schema compare between your source controlled version of the database and the version in production is a breeze. And with a click you can generate your diff DDL.
There's an instructional video on MSDN that's very helpful.
I know about DBMS_METADATA and Toad, but if someone could come up with a Data Dude for Oracle then life would be really sweet.

Have your initial create table statements in version controller, then add alter table statements, but never edit files, just more alter files ideally named sequentially, or even as a "change set", so you can find all the changes for a particular deployment.
The hardiest part that I can see, is tracking dependencies, eg, for a particular deployment table B might need to be updated before table A.

For Oracle, I use Toad, which can dump a schema to a number of discrete files (e.g., one file per table). I have some scripts that manage this collection in Perforce, but I think it should be easily doable in just about any revision control system.

Take a look at the oracle package DBMS_METADATA.
In particular, the following methods are particularly useful:
DBMS_METADATA.GET_DDL
DBMS_METADATA.SET_TRANSFORM_PARAM
DBMS_METADATA.GET_GRANTED_DDL
Once you are familiar with how they work (pretty self explanatory) you can write a simple script to dump the results of those methods into text files that can be put under source control. Good luck!
Not sure if there is something this simple for MSSQL.

I write my db release scripts in parallel with coding, and keep the release scripts in a project specific section in SS. If I make a change to the code that requires a db change, then I update the release script at the same time.
Prior to release, I run the release script on a clean dev db (copied structure wise from production) and do my final testing on it.

I've done this off and on for years -- managing (or trying to manage) schema versions. The best approaches depend on the tools you have. If you can get the Quest Software tool "Schema Manager" you'll be in good shape. Oracle has its own, inferior tool that is also called "Schema Manager" (confusing much?) that I don't recommend.
Without an automated tool (see other comments here about Data Dude) then you'll be using scripts and DDL files directly. Pick an approach, document it, and follow it rigorously. I like having the ability to re-create the database at any given moment, so I prefer to have a full DDL export of the entire database (if I'm the DBA), or of the developer schema (if I'm in product-development mode).

PLSQL Developer, a tool from All Arround Automations, has a plugin for repositories that works OK ( but not great) with Visual Source Safe.
From the web:
The Version Control Plug-In provides a tight integration between the PL/SQL Developer IDE >>and any Version Control System that supports the Microsoft SCC Interface Specification. >>This includes most popular Version Control Systems such as Microsoft Visual SourceSafe, >>Merant PVCS and MKS Source Integrity.
http://www.allroundautomations.com/plsvcs.html

ER Studio allows you to reverse your database schema into the tool and you can then compare it to live databases.
Example: Reverse your development schema into ER Studio -- compare it to production and it will list all of the differences. It can script the changes or just push them through automatically.
Once you have a schema in ER Studio, you can either save the creation script or save it as a proprietary binary and save it in version control. If you ever want to go back to a past version of the scheme, just check it out and push it to your db platform.

There's a PHP5 "database migration framework" called Ruckusing. I haven't used it, but the examples show the idea, if you use the language to create the database as and when needed, you only have to track source files.

We've used MS Team System Database Edition with pretty good success. It integrates with TFS version control and Visual Studio more-or-less seamlessly and allows us to manages stored procs, views, etc., easily. Conflict resolution can be a pain, but version history is complete once it's done. Thereafter, migrations to QA and production are extremely simple.
It's fair to say that it's a version 1.0 product, though, and is not without a few issues.

You can use Microsoft SQL Server Data Tools in visual studio to generate scripts for database objects as part of a SQL Server Project. You can then add the scripts to source control using the source control integration that is built into visual studio. Also, SQL Server Projects allow you verify the database objects using a compiler and generate deployment scripts to update an existing database or create a new one.

In the absence of a VCS for table changes I've been logging them in a wiki. At least then I can see when and why it was changed. It's far from perfect as not everyone is doing it and we have multiple product versions in use, but better than nothing.

I'd recommend one of two approaches. First, invest in PowerDesigner from Sybase. Enterprise Edition. It allows you to design Physical datamodels, and a whole lot more. But it comes with a repository that allows you to check in your models. Each new check in can be a new version, it can compare any version to any other version and even to what is in your database at that time. It will then present a list of every difference and ask which should be migrated… and then it builds the script to do it. It’s not cheap but it’s a bargain at twice the price and it’s ROI is about 6 months.
The other idea is to turn on DDL auditing (works in Oracle). This will create a table with every change you make. If you query the changes from the timestamp you last moved your database changes to prod to right now, you’ll have an ordered list of everything you’ve done. A few where clauses to eliminate zero-sum changes like create table foo; followed by drop table foo; and you can EASILY build a mod script. Why keep the changes in a wiki, that’s double the work. Let the database track them for you.

Schema Compare for Oracle is a tool specifically designed to migrate changes from our Oracle database to another. Please visit the URL below for the download link, where you will be able to use the software for a fully functional trial.
http://www.red-gate.com/Products/schema_compare_for_oracle/index.htm

Two book recommendations: "Refactoring Databases" by Ambler and Sadalage and "Agile Database Techniques" by Ambler.
Someone mentioned Rails Migrations. I think they work great, even outside of Rails applications. I used them on an ASP application with SQL Server which we were in the process of moving to Rails. You check the migration scripts themselves into the VCS.
Here's a post by Pragmatic Dave Thomas on the subject.

Related

Track changes made to a database

Background:
I have a MS SQL Server database and I want to track changes to it. For example if a column needed to be added or removed or a table needed to be dropped. Something similar to Version control for regular code.
The problem:
While looking around I saw that there were some tools that can be used:
RedGate SQL Source Control
Visual Studio Database project
I am more interested in knowing if either of these tools will track changes to my database? More specifically I have a TFS server that is the source control for my MVC code, can I use either of these with TFS? Will it allow us to restore from older versions? Will it allow multiple developers to work on the database simultaneously?
For this type of work, ApexSQL Source Control shown to be all that you need. With this SSMS add-in you can work directly on a database, and all of your changes will be tracked in real time.
Yes, several developers can work in the same time on the same database. When one developer works on a one or several objects, other developers can see which those objects are, and until the first one does not finish changing the others cannot change that object, they will not be allowed to.
If by any case, object is changed wrong, previous version or any earlier version can be restored at any moment.
This add-in has all necessary options and features to allow the developers to work without losing time for checking changes made against object, since the add-in does that for them. And you can always see by whom, when and what that change is.
Being in the database version control space for 5 years (as director of product management at DBmaestro) and having worked as a DBA for over two decades, I can tell you the simple fact that you cannot treat the database objects as you treat your Java, C# or other files and save the changes in simple DDL scripts.
There are many reasons and I'll name a few:
Files are stored locally on the developer’s PC and the change s/he
makes do not affect other developers. Likewise, the developer is not
affected by changes made by her colleague. In database this is
(usually) not the case and developers share the same database
environment, so any change that were committed to the database affect
others.
Publishing code changes is done using the Check-In / Submit Changes /
etc. (depending on which source control tool you use). At that point,
the code from the local directory of the developer is inserted into
the source control repository. Developer who wants to get the latest
code need to request it from the source control tool. In database
the change already exists and impacts other data even if it was not
checked-in into the repository.
During the file check-in, the source control tool performs a conflict
check to see if the same file was modified and checked-in by another
developer during the time you modified your local copy. Again there
is no check for this in the database. If you alter a procedure from
your local PC and at the same time I modify the same procedure with
code form my local PC then we override each other’s changes.
The build process of code is done by getting the label / latest
version of the code to an empty directory and then perform a build –
compile. The output are binaries in which we copy & replace the
existing. We don't care what was before. In database we cannot
recreate the database as we need to maintain the data! Also the
deployment executes SQL scripts which were generated in the build
process.
When executing the SQL scripts (with the DDL, DCL, DML (for static
content) commands) you assume the current structure of the
environment match the structure when you create the scripts. If not,
then your scripts can fail as you are trying to add new column which
already exists.
Treating SQL scripts as code and manually generating them will cause
syntax errors, database dependencies errors, scripts that are not
reusable which complicate the task of developing, maintaining,
testing those scripts. In addition, those scripts may run on an
environment which is different from the one you though it would run
on.
Sometimes the script in the version control repository does not match
the structure of the object that was tested and then errors will
happen in production!
There are many more, but I think you got the picture.
What I found that works is the following:
Use an enforced version control system that enforces
check-out/check-in operations on the database objects. This will
make sure the version control repository matches the code that was
checked-in as it reads the metadata of the object in the check-in
operation and not as a separated step done manually. This also allow
several developers to work in parallel on the same database while
preventing them to accidently override each other code.
Use an impact analysis that utilize baselines as part of the
comparison to identify conflicts and identify if a change (when
comparing the object's structure between the source control
repository and the database) is a real change that origin from
development or a change that was origin from a different path and
then it should be skipped, such as different branch or an emergency
fix.
An article I wrote on this was published here, you are welcome to read it.
If you're looking for a product that will track changes into TFS from your SQL Server automatically, I'd invite you take a look at our product, Sql Historian. It's different from most other SQL version control systems (including the ones you've listed) in that it does not require developers to perform a check-in ritual to synchronize version control with what's already committed to the db.
However, features common with Sql Historian and the other two systems you mention are: working with TFS, the ability to view older versions of your db objects, and allowing multiple users on the db at the same time.

Visual Studio 2013 SQL Server Project Deployment/Publish

I am looking for information regarding Visual Studio 2013 and working with SQL Server projects using VS 2013. We are currently working on a project where were're using a database that already exists and is used by an ERP application. We're creating SQL Scripts that would alter and create fields on a table on the target database.
Now, we're not looking to "publish" those scripts, but create postdeploy scripts instead, which contains all the necessary SQL scripts in the order they need to be run. Everything is working fine. When we build the project, we get a fresh copy of the PostDeploy.sql script file that we run across a target database.
At the moment, the script looks at a table, if the column that needs to be added exists, it DROPS it and then recreates it. This is fine for the testing phase, but once we go live, there will be several stages of the databases that the code needs to be tested on. The column may already exist from before and in that case, we wouldn't want to DROP that column, instead, we want to do schema and data level compare and just get over the objects that are DIFFERENT, so that the column doesn't need to be dropped, instead just "updated". I hope I am not being vague when I ask this question.
I found this video: https://www.youtube.com/watch?v=AuVpmu9CKRY and I am not sure if that is what I need to do? I would love any suggestions from you guys..
Have a wonderful day!
Well, this isn't really the best use for SSDT/DB Projects. Ideally, you'd want to pull the schema into a project and tweak that project to look the way you want. Rename columns, change types, etc. Because it sounds like this is a 3rd party app, you'd want some environment that can serve as your baseline - when you run whatever upgrade script is sent by the vendor, it goes against that environment. You'd then want to pull the appropriate changes into your project.
Once you have a project that looks the way you want, you use the publish option against your target database. In your case, I'd likely recommend generating a script. If you're in the VS environment, you can take a look at both the script and a summary of what will be changed.
For data compares, I'd really consider something like Red Gate's SQL Data Compare (pro edition if you can). You can set up a data compare against your baseline and automate pushing the data changes. You can do that through post-deploy scripts, but you'll need to hand-code the data inserts, updates, and deletes yourself.
I've blogged about SSDT before and that may give you some ideas. Jamie Thomson has also written quite a bit about Database/SQL Projects and inspired quite a bit of what I've done.
http://schottsql.blogspot.com/2013/10/all-ssdt-articles.html

SQL SERVER Project

My Application Database Without Project and without Source safe, i planned to make my DB to be as project and add it to TFS, but I have no idea how to script the stored procedures, Triggers, Views, Functions, and what is the best practice to Make Update Script for All My stored procedures, Triggers, Views, and Functions to My customers DB.
The best procedure (IMHO) is to manually maintain a strict version of your schemas. Then when you need to make changes you write a delta script to move from one version to the next. I suggest you write the DDL scripts by hand -- you can make them concise and comment them.
You can use a tool like Visual Studio Team System for database architects, take a look at Running static code analysis on SQL Server database with Visual Studio Team System for database architects it will show you how to import the data, disregard the static code analysis that comes later it does not apply to your question
I've found a good way to get SQL scripts into SCM from an existing database is to use SMSS's "export all to script" option or whatever it's called, can't remember now.
Then every other change you add the change script into your SCM with a different version number in the file name.
Every release (or set cycle depending on your development/release methodology) you apply all change scripts, then re-script the entire database, tag it, and start again.
The best way to do it - save the database in TFS as set of database creation script, i.e. MyTable table should be added to TFS as MyTable.sql file (CREATE TABLE...) etc. We are using SQL Examiner to do this - see the following article: How to keep your database under version control
We are working with SVN and I never tested SQL Examiner with TFS, but I know that the tool supports TFS.

Creating a CHANGE script in Management Studio?

I was wondering if there is a way to automatically append to a script file all the changes I am making to my columns, tables, relationships etc...
The thing is I am doing a lot of different changes on a TEST db and the idea will be to apply this change script when I move the test db to production... hence keeping production data but applying all schema and object changes.
Is there an easy way to do this? Can it also migrate database diagram changes?
I have seen how you can create a change script each time I do a change but this means I have to copy and paste into a master file. Actually pretty easy!
I was just wondering if I was missing something?
Do not make changes to the test server using the UI. Write scripts and keep them under source control. You can test your scripts starting from backups of the live data and you can tune yoru scripts untill they achieve the desired result. Then you can check in the scripts for reference and later apply them on the live server. See this article Version Control and Your Database.
BTW, check out the SSMS toolpack, I think it may do what you want (I'm not sure). My advice stand none the less: version your schema, use explicitly created/saved scripts, use source control.
There's no way to directly generate a "delta" script in SSMS.
However, if every time you publish changes, you script out the entire database, including data, to SQL using the SQL Server Database Publishing Wizard you should be able to extract diffs between the versions and get your deltas that way.
If money is no object, you can purchase Visual Studio Team System Database Architect edition and use its fantastic database comparison tools to generate and version control exactly the diffs you want.
Try using TableDiff , that came with SQL Server 2005.
SQL Server 2005 TableDiff Utility
tablediff Utility
We have the process where when a developer gets done with a change, they then script it out and check it into Subversion. In Subversion we have a folder for Tables, Stored Procs, Data, etc. They script it out so it is repeatable (i.e. don’t insert the new data if it is already there.) This is important to do anyway so you keep the history of changes for a given object in the database.
In the past, we would just enter each of the files that we wanted scripted out into a text file (i.e. FileListV102.txt). When we were ready to make a release we would do “get latest” on all of the files (from VSS back then.) We then had a simple utility that would read the “file list” file and open each of those files in turn concatenating them into an output file. That is pretty easy to code.
We outgrew that and now we have a release management tools (which can be found here and will be on sale mid September), that takes all of the files and creates a big SQL script file out of it. It does it in the order that you would expect based on the folder names – so files found in the "Tables" folder are done before those in the "Data" folder, etc.
Either way, once you are done you have a big SQL script file that you can then apply to a fresh copy of production and that is what you test against.
I know I'm way late to the party, but I just wanted to add that there are tens of third party products out there. Some are very good, some are very cheap or free, and some are a mixture. I listed 22 here:
http://bertrandaaron.wordpress.com/2012/04/20/re-blog-the-cost-of-reinventing-the-wheel/
We have been using a relatively new software called Kal Admin.
It has Change Management feature and let distributing selected changes to other databases very easily. We used to do it by comparing two databases but it not satisfy our need for change tracking.
BTW Kal Admin has Metadata and data compare capabilities as well.

Best way to version control T-SQL? [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Stored procedures/DB schema in source control
What's the best way to version control my tables, views, sprocs, etc? Preferably automated or at least semi-automated :)
Thanks
I asked this one yesterday and got some nice responses:
Stored procedures/DB schema in source control
The articles from K Scott Allen say it all:
http://odetocode.com/Blogs/scott/archive/2008/01/31/11710.aspx
Write migration scripts for all db changes and keep them in a repository. Enforce a policy of making all changes to the db only by running a script; that way there is a record of what has been done, and a way to revert it. Investigate whether there's a migrations framework available for your favorite language/db combination.
I use Visual Studio 2008 Pro create Database projects (Other project types -> Database). We already use SVN as a code repository, so a project with a bunch of .sql files representing your stored procedures is just another thing to put in the repository - you can see diffs/history etc. This works the same with VSS or any other repository you use.
The nice thing about Database projects is that your project will remember your connection string, and all you have to do is right click on a .sql file (or select all of them at once!) and select run to update it in the db. This makes it easy to update your .sql files from the repository and run them all to update all your stored procedures, verifying your database is updated in seconds.
You can also select create a LINQ project (Visual C# -> Database) and store all your LINQ code in your repository.
Hope that helps!
If you were super lazy you could use the SMO (SQL Server Management Objects) or if using SQL Server prior to 2005 the DMO (distributed managmeent objects) to script out all tables/views/stored procedures daily and then compare the script to the script in source control and if there are any changes check the new version in. You won't be able to necessarily have as pretty of a script as if you just created all db changes in scripts, but at least you can recreate all tables/stored procedures/views. For example, in my table creation scripts there are often comments.
Here is an article to get you started on scripting: http://www.sqlteam.com/article/scripting-database-objects-using-smo-updated.
Again, this is mainly if you are too lazy to bother with version control and it won't help if you change something twice in one day. Also any data migration scripts still have to be saved and checked in because this won't pick up ad hoc SQL, only database objects.
I have written a DDL trigger which logs all the changes done to the definition of SQL objects (triggers, tables, SP, view etc). I could very well invoke extended SP from the trigger and store the details in another Database and use that as repository.
But if your team is really disciplined any source control should do the trick. The trigger is used as an audit mechanism and it's ideal for teams which are geographically scattered.
Try Randolph, One of the best SQL Version control tools I know.
I'm using Visual Studio Database edition which can export the schema from SQL Server in to a Visual Studio project. This is then stored in Source Control and can be deployed where ever needed. The VS Database project is just a bunch of scripts though and it's a clunky way of working.
A more robust method would be to use a database migration framework and if you're working with .Net check out this blog post for a good description http://flux88.com/NETDatabaseMigrationToolRoundup.aspx.
Update
As mentioned in the comments, this page is no more. So here is the last known snapshot from wayback machine http://web.archive.org/web/20080828232742/http://flux88.com/NETDatabaseMigrationToolRoundup.aspx