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I would like to know how you guys deal with development database changes in groups of 2 or more devs? Do you have a global db everyone access, maybe a local copy and manually apply script changes? It would be nice to see pros and cons that you've noticed for each approach and the number of devs in your team.
Start with "Evolutionary Database Design" by Martin Fowler. This sums it up nicely
There are have been other questions about DB development that may be useful too, for example Is RedGate SQL Source Control for me?
Our approach is that everyone has their own DB, the complete DB can be created from create scripts with base data if required. All the scripts required for this are in source control.
All scripts are CREATE scripts and they reflect the current state of the database schema. Upgrades are in separate SQL files which can upgrade existing DBs from a specific version to a newer one (run sequentially). After all the updates have been applied, the schema must be identical to what you would get from running the setup scripts.
We have some tools to do this (we use SQL Server and .NET):
Scripting is done with a tool which also applies a standard formatting so that the changes are well traceable with text diff tools (and by the SCM)
A runtime module takes care of comparing the existing DB objects, run updates if required, automatically apply "non-destructive" changes, then check the DB objects again to ensure a correct migration before committing the changes
The toolset is available as open-source project (licensed under LGPL), it's called the bsn ModuleStore (note that it is limited to SQL Server 2005/2008/Azure and to .NET for the runtime part).
We use what was code named "Data Dude" - the database features in TFS and Visual Studio - to deal with this. When you "get latest" and bring in code that relies on a schema change, you also bring in the revised schemas, stored procedures etc. You rigght-click the database project and Deploy; that gets your local schema and sp in sync but doesn't overwrite your data. The job of working out the script to get you from your old schema to the new one falls to Visual Studio, not to you or your DBA. We also have "populate" scripts for things like lists of provinces and a deploy runs them for you.
So much better than the old way which always fell apart at high stress times, with people checking in code then going home and nobody knowing what columns to add to make the code work etc.
Building and maintaining a database that is then deplyed/developed further by many devs is something that goes on in software development all the time. We create a build script, and maintain further update scripts that get applied as the database grows over time. There are many ways to manage this, from manual updates to console apps/build scripts that help automate these processes.
Has anyone who has built/managed these processes moved over to a Source Control solution for database schema management? If so, what have they found the best solution to be? Are there any pitfalls that should be avoided?
Red Gate seems to be a big player in the MSSQL world and their DB source control looks very interesting:
http://www.red-gate.com/products/solutions_for_sql/database_version_control.htm
Although it does not look like it replaces the (default) data* management process, so it only replaces half the change management process from my pov.
(when I'm talking about data, I mean lookup values and that sort of thing, data that needs to be deployed by default or in a DR scenario)
We work in a .Net/MSSQL environment, but I'm sure the premise is the same across all languages.
Similar Questions
One or more of these existing questions might be helpful:
The best way to manage database changes
MySQL database change tracking
SQL Server database change workflow best practices
Verify database changes (version-control)
Transferring changes from a dev DB to a production DB
tracking changes made in database structure
Or a search for Database Change
I look after a data warehouse developed in-house by the bank where I work. This requires constant updating, and we have a team of 2-4 devs working on it.
We are fortunate because there is only the one instance of our "product", so we do not have to cater for deploying to multiple instances which may be at different versions.
We keep a creation script file for each object (table, view, index, stored procedure, trigger) in the database.
We avoid the use of ALTER TABLE whenever possible, preferring to rename a table, create the new one and migrate the data over. This means that we don't have to look through a history of ALTER scripts - we can always see the up to date version of every table by looking at its create script. The migration is performed by a separate migration script - this can be partly auto-generated.
Each time we do a release, we have a script which runs the create scripts / migration scripts in the appropriate order.
FYI: We use Visual SourceSafe (yuck!) for source code control.
I've been looking for a SQL Server source control tool - and came across a lot of premium versions that do the job - using SQL Server Management Studio as a plugin.
LiquiBase is a free one but i never quite got it working for my needs.
There is another free product out there though that works stand along from SSMS and scripts out objects and data to flat file.
These objects can then be pumped into a new SQL Server instance which will then re-create the database objects.
See gitSQL
Maybe you're asking for LiquiBase?
I have been working on a project and gotten it through the first stage. However, the requirments ended up changing and I have to add new tables and redo some of the foriegn key references in the DB.
The problem I have is my lack of knowledge of dealing with doing this kind of change to a staging then production database once I get the development done on dev database.
What are some strategies for migrating database schema changes and maintaining data in the database?
About as far as my knowledge is on doing this is open up Sql Server Management Studio and starting adding tables manually. I know this is probably a bad way to do it so looking for how to do it properly while realizing I probably started out wrong.
For maintaining schema changes you can use ApexSQL Diff, a SQL Server and SQL Azure schema comparison and synchronization tool, and for maintaining data in the database you can use ApexSQL Data Diff, a SQL Server and SQL Azure data comparison and synchronization tool.
Hope this helps
Disclaimer: I work for ApexSQL as a Support Engineer
You have to have something called as a "KIT". Obviously, if you are maintaining some kind of a source control, all the scripts for the changes that you do in the development environments should be maintained in the source control configuration tool.
Once you are done with all the scripts/changes that you deem certified to move to next higher environment. Prepare the kit with having all these scripts in folders (ideally categorized as Procedures, Tables, Functions, Bootstraps) And then have a batch files that could execute these scripts in the kit in a particular order using OSQL command line utility.
Have separate batch files for UAT/ Staging/ production so that you can just double click on the batch file to execute the kit in the appropriate server. Check for OSQL options.
This way all your environments are in sync!
I typically use something like the SQL Server Publishing Wizard to produce SQL scripts of the changes. That is a rather simple and easy approach. The major downside with that tool is that the produced will drop and recreate tables that are not changed but used by procedures that have changed (and I can't understand why), so there is some manual labour involved in going through the script and remove things that don't need to be there.
Note that you don't need to download and install this tool; you can launch it from within Visual Studio. Right-click on a connection in the Server Explorer and select "Publish to Provider" in the context menu.
Red Gate SQL Compare and SQL Data Compare all the way. Since my company bought it, it saved me tons of time staging our databases from DEV to TEST to ACCEPTANCE to PRODUCTION.
And you can have it synchronize with a scripts folder too for easy integration in a source control system.
http://www.red-gate.com
You might want to check out a tool like Liquibase: http://liquibase.org/
You can use visual studio 2015. Go to Tools=> SQL server => New Schema comparison
step 1) Select source and target Database.
Click on Compare option.
step 2) once comparison completed, you can click on icon Generate Script(Shift+alt+G)
this will generate Commit script.
step 3) To generate rollback script for database changes just swap database from step 1
There are some tools available to help you with that.
If you have Visual Studio Team edition, check database projects (aka DataDude aka Visual Studio Team for Database Professionals) See here and here
It allows you to generate a model from the dev/integration database and then (for many, but not all cases) automatically create scripts which update your prod database with the changes you made to dev/integration.
For VS 2008, make sure you get the GDR2 patches.
We have found the best way to push changes is to treat databases changes like code. All changes are in scripts, they are in source control and they are part of a version. Nothing is ever under any circumstances pushed to prod that is not scripted and in source control. That way you don't accidentally push changes that are in dev, but not yet ready to be pushed to prod. Further you can restore prod data to the dev box and rerun all the scripts not yet pushed and you have fresh data and all the dev work preserved. This also works great when you have lookup values to tables that are chaging that you don;t want pushed to prod until other things move as well. Script the insert and put it with the rest of the code for the version.
It's nice to use those tools to do a compare to see if something is missed in the scripts, but I would NEVER rely on them alone. Far too much risk of pushing something "not yet ready for prime time" to prod.
A good database design tool (such as Sybase Powerdesigner) will allow you to create the design changes to the data model, then generate the code to implement those changes. You can then store and run the code as you choose. This tool should also be able to do reverse engineering when you inherit a database you didn't build.
Finding all the changes between development and production is often difficult even in an organized, well-documented environment. Idera has a tool for SQL Server which will detect structural differences between your development and production database and another tool which detects changes in the data. In fact, I often use these to go the other direction and sync development with production to start a new project.
I have read lots of posts about the importance of database version control. However, I could not find a simple solution how to check if database is in state that it should be.
For example, I have a databases with a table called "Version" (version number is being stored there). But database can be accessed and edited by developers without changing version number. If for example developer updates stored procedure and does not update Version database state is not in sync with version value.
How to track those changes? I do not need to track what is changed but only need to check if database tables, views, procedures, etc. are in sync with database version that is saved in Version table.
Why I need this? When doing deployment I need to check that database is "correct". Also, not all tables or other database objects should be tracked. Is it possible to check without using triggers? Is it possible to be done without 3rd party tools? Do databases have checksums?
Lets say that we use SQL Server 2005.
Edited:
I think I should provide a bit more information about our current environment - we have a "baseline" with all scripts needed to create base version (includes data objects and "metadata" for our app). However, there are many installations of this "base" version with some additional database objects (additional tables, views, procedures, etc.). When we make some change in "base" version we also have to update some installations (not all) - at that time we have to check that "base" is in correct state.
Thanks
You seem to be breaking the first and second rule of "Three rules for database work". Using one database per developer and a single authoritative source for your schema would already help a lot. Then, I'm not sure that you have a Baseline for your database and, even more important, that you are using change scripts. Finally, you might find some other answers in Views, Stored Procedures and the Like and in Branching and Merging.
Actually, all these links are mentioned in this great article from Jeff Atwood: Get Your Database Under Version Control. A must read IMHO.
We use DBGhost to version control the database. The scripts to create the current database are stored in TFS (along with the source code) and then DBGhost is used to generate a delta script to upgrade an environment to the current version. DBGhost can also create delta scripts for any static/reference/code data.
It requires a mind shift from the traditional method but is a fantastic solution which I cannot recommend enough. Whilst it is a 3rd party product it fits seamlessly into our automated build and deployment process.
I'm using a simple VBScript file based on this codeproject article to generate drop/create scripts for all database objects. I then put these scripts under version control.
So to check whether a database is up-to-date or has changes which were not yet put into version control, I do this:
get the latest version of the drop/create scripts from version control (subversion in our case)
execute the SqlExtract script for the database to be checked, overwriting the scripts from version control
now I can check with my subversion client (TortoiseSVN) which files don't match with the version under version control
now either update the database or put the modified scripts under version control
You have to restrict access to all databases and only give developers access to a local database (where they develop) and to the dev server where they can do integration. The best thing would be for them to only have access to their dev area locally and perform integration tasks with an automated build. You can use tools like redgates sql compare to do diffs on databases. I suggest that you keep all of your changes under source control (.sql files) so that you will have a running history of who did what when and so that you can revert db changes when needed.
I also like to be able to have the devs run a local build script to re initiate their local dev box. This way they can always roll back. More importantly they can create integration tests that tests the plumbing of their app (repository and data access) and logic stashed away in a stored procedure in an automated way. Initialization is ran (resetting db), integration tests are ran (creating fluff in the db), reinitialization to put db back to clean state, etc.
If you are an SVN/nant style user (or similar) with a single branch concept in your repository then you can read my articles on this topic over at DotNetSlackers: http://dotnetslackers.com/articles/aspnet/Building-a-StackOverflow-inspired-Knowledge-Exchange-Build-automation-with-NAnt.aspx and http://dotnetslackers.com/articles/aspnet/Building-a-StackOverflow-inspired-Knowledge-Exchange-Continuous-integration-with-CruiseControl-NET.aspx.
If you are a perforce multi branch sort of build master then you will have to wait till I write something about that sort of automation and configuration management.
UPDATE
#Sazug: "Yep, we use some sort of multi branch builds when we use base script + additional scripts :) Any basic tips for that sort of automation without full article?" There are most commonly two forms of databases:
you control the db in a new non-production type environment (active dev only)
a production environment where you have live data accumulating as you develop
The first set up is much easier and can be fully automated from dev to prod and to include rolling back prod if need be. For this you simply need a scripts folder where every modification to your database can be maintained in a .sql file. I don't suggest that you keep a tablename.sql file and then version it like you would a .cs file where updates to that sql artifact is actually modified in the same file over time. Given that sql objects are so heavily dependent on each other. When you build up your database from scratch your scripts may encounter a breaking change. For this reason I suggest that you keep a separate and new file for each modification with a sequence number at the front of the file name. For example something like 000024-ModifiedAccountsTable.sql. Then you can use a custom task or something out of NAntContrib or an direct execution of one of the many ??SQL.exe command line tools to run all of your scripts against an empty database from 000001-fileName.sql through to the last file in the updateScripts folder. All of these scripts are then checked in to your version control. And since you always start from a clean db you can always roll back if someones new sql breaks the build.
In the second environment automation is not always the best route given that you might impact production. If you are actively developing against/for a production environment then you really need a multi-branch/environment so that you can test your automation way before you actually push against a prod environment. You can use the same concepts as stated above. However, you can't really start from scratch on a prod db and rolling back is more difficult. For this reason I suggest using RedGate SQL Compare of similar in your build process. The .sql scripts are checked in for updating purposes but you need to automate a diff between your staging db and prod db prior to running the updates. You can then attempt to sync changes and roll back prod if problems occur. Also, some form of a back up should be taken prior to an automated push of sql changes. Be careful when doing anything without a watchful human eye in production! If you do true continuous integration in all of your dev/qual/staging/performance environments and then have a few manual steps when pushing to production...that really isn't that bad!
First point: it's hard to keep things in order without "regulations".
Or for your example - developers changing anything without a notice will bring you to serious problems.
Anyhow - you say "without using triggers".
Any specific reason for this?
If not - check out DDL Triggers. Such triggers are the easiest way to check if something happened.
And you can even log WHAT was going on.
Hopefully someone has a better solution than this, but I do this using a couple methods:
Have a "trunk" database, which is the current development version. All work is done here as it is being prepared to be included in a release.
Every time a release is done:
The last release's "clean" database is copied to the new one, eg, "DB_1.0.4_clean"
SQL-Compare is used to copy the changes from trunk to the 1.0.4_clean - this also allows checking exactly what gets included.
SQL Compare is used again to find the differences between the previous and new releases (changes from DB_1.0.4_clean to DB_1.0.3_clean), which creates a change script "1.0.3 to 1.0.4.sql".
We are still building the tool to automate this part, but the goal is that there is a table to track every version the database has been at, and if the change script was applied. The upgrade tool looks for the latest entry, then applies each upgrade script one-by-one and finally the DB is at the latest version.
I don't have this problem, but it would be trivial to protect the _clean databases from modification by other team members. Additionally, because I use SQL Compare after the fact to generate the change scripts, there is no need for developers to keep track of them as they go.
We actually did this for a while, and it was a HUGE pain. It was easy to forget, and at the same time, there were changes being done that didn't necessarily make it - so the full upgrade script created using the individually-created change scripts would sometimes add a field, then remove it, all in one release. This can obviously be pretty painful if there are index changes, etc.
The nice thing about SQL compare is the script it generates is in a transaction -and it if fails, it rolls the whole thing back. So if the production DB has been modified in some way, the upgrade will fail, and then the deployment team can actually use SQL Compare on the production DB against the _clean db, and manually fix the changes. We've only had to do this once or twice (damn customers).
The .SQL change scripts (generated by SQL Compare) get stored in our version control system (subversion).
If you have Visual Studio (specifically the Database edition), there is a Database Project that you can create and point it to a SQL Server database. The project will load the schema and basically offer you a lot of other features. It behaves just like a code project. It also offers you the advantage to script the entire table and contents so you can keep it under Subversion.
When you build the project, it validates that the database has integrity. It's quite smart.
On one of our projects we had stored database version inside database.
Each change to database structure was scripted into separate sql file which incremented database version besides all other changes. This was done by developer who changed db structure.
Deployment script checked against current db version and latest changes script and applied these sql scripts if necessary.
Firstly, your production database should either not be accessible to developers, or the developers (and everyone else) should be under strict instructions that no changes of any kind are made to production systems outside of a change-control system.
Change-control is vital in any system that you expect to work (Where there is >1 engineer involved in the entire system).
Each developer should have their own test system; if they want to make changes to that, they can, but system tesing should be done on a more controlled, system test system which has the same changes applied as production - if you don't do this, you can't rely on releases working because they're being tested in an incompatible environment.
When a change is made, the appropriate scripts should be created and tested to ensure that they apply cleanly on top of the current version, and that the rollback works*
*you are writing rollback scripts, right?
I agree with other posts that developers should not have permissions to change the production database. Either the developers should be sharing a common development database (and risk treading on each others' toes) or they should have their own individual databases. In the former case you can use a tool like SQL Compare to deploy to production. In the latter case, you need to periodically sync up the developer databases during the development lifecycle before promoting to production.
Here at Red Gate we are shortly going to release a new tool, SQL Source Control, designed to make this process a lot easier. We will integrate into SSMS and enable the adding and retrieving objects to and from source control at the click of a button. If you're interested in finding out more or signing up to our Early Access Program, please visit this page:
http://www.red-gate.com/Products/SQL_Source_Control/index.htm
I have to agree with the rest of the post. Database access restrictions would solve the issue on production. Then using a versioning tool like DBGhost or DVC would help you and the rest of the team to maintain the database versioning
I wonder how you guys manage deployment of a database between 2 SQL Servers, specifically SQL Server 2005.
Now, there is a development and a live one. As this should be part of a buildscript (standard windows batch, even do with current complexity of those scripts, i might switch to PowerShell or so later), Enterprise Manager/Management Studio Express do not count.
Would you just copy the .mdf File and attach it? I am always a bit careful when working with binary data, as this seems to be a compatiblity issue (even though development and live should run the same version of the server at all time).
Or - given the lack of "EXPLAIN CREATE TABLE" in T-SQL - do you do something that exports an existing database into SQL-Scripts which you can run on the target server? If yes, is there a tool that can automatically dump a given Database into SQL Queries and that runs off the command line? (Again, Enterprise Manager/Management Studio Express do not count).
And lastly - given the fact that the live database already contains data, the deployment may not involve creating all tables but rather checking the difference in structure and ALTER TABLE the live ones instead, which may also need data verification/conversion when existing fields change.
Now, i hear a lot of great stuff about the Red Gate products, but for hobby projects, the price is a bit steep.
So, what are you using to automatically deploy SQL Server Databases from Test to Live?
I've taken to hand-coding all of my DDL (creates/alter/delete) statements, adding them to my .sln as text files, and using normal versioning (using subversion, but any revision control should work). This way, I not only get the benefit of versioning, but updating live from dev/stage is the same process for code and database - tags, branches and so on work all the same.
Otherwise, I agree redgate is expensive if you don't have a company buying it for you. If you can get a company to buy it for you though, it really is worth it!
For my projects I alternate between SQL Compare from REd Gate and the Database Publishing Wizard from Microsoft which you can download free
here.
The Wizard isn't as slick as SQL Compare or SQL Data Compare but it does the trick. One issue is that the scripts it generates may need some rearranging and/or editing to flow in one shot.
On the up side, it can move your schema and data which isn't bad for a free tool.
Don't forget Microsoft's solution to the problem: Visual Studio 2008 Database Edition. Includes tools for deploying changes to databases, producing a diff between databases for schema and/or data changes, unit tests, test data generation.
It's pretty expensive but I used the trial edition for a while and thought it was brilliant. It makes the database as easy to work with as any other piece of code.
Like Rob Allen, I use SQL Compare / Data Compare by Redgate. I also use the Database publishing wizard by Microsoft. I also have a console app I wrote in C# that takes a sql script and runs it on a server. This way you can run large scripts with 'GO' commands in it from a command line or in a batch script.
I use Microsoft.SqlServer.BatchParser.dll and Microsoft.SqlServer.ConnectionInfo.dll libraries in the console application.
I work the same way Karl does, by keeping all of my SQL scripts for creating and altering tables in a text file that I keep in source control. In fact, to avoid the problem of having to have a script examine the live database to determine what ALTERs to run, I usually work like this:
On the first version, I place everything during testing into one SQL script, and treat all tables as a CREATE. This means I end up dropping and readding tables a lot during testing, but that's not a big deal early into the project (since I'm usually hacking the data I'm using at that point anyway).
On all subsequent versions, I do two things: I make a new text file to hold the upgrade SQL scripts, that contain just the ALTERs for that version. And I make the changes to the original, create a fresh database script as well. This way an upgrade just runs the upgrade script, but if we have to recreate the DB we don't need to run 100 scripts to get there.
Depending on how I'm deploying the DB changes, I'll also usually put a version table in the DB that holds the version of the DB. Then, rather than make any human decisions about which scripts to run, whatever code I have running the create/upgrade scripts uses the version to determine what to run.
The one thing this will not do is help if part of what you're moving from test to production is data, but if you want to manage structure and not pay for a nice, but expensive DB management package, is really not very difficult. I've also found it's a pretty good way of keeping mental track of your DB.
If you have a company buying it, Toad from Quest Software has this kind of management functionality built in. It's basically a two-click operation to compare two schemas and generate a sync script from one to the other.
They have editions for most of the popular databases, including of course Sql Server.
I agree that scripting everything is the best way to go and is what I advocate at work. You should script everything from DB and object creation to populating your lookup tables.
Anything you do in UI only won't translate (especially for changes... not so much for first deployments) and will end up requiring a tools like what Redgate offers.
Using SMO/DMO, it isn't too difficult to generate a script of your schema. Data is a little more fun, but still doable.
In general, I take "Script It" approach, but you might want to consider something along these lines:
Distinguish between Development and Staging, such that you can Develop with a subset of data ... this I would create a tool to simply pull down some production data, or generate fake data where security is concerned.
For team development, each change to the database will have to be coordinated amongst your team members. Schema and data changes can be intermingled, but a single script should enable a given feature. Once all your features are ready, you bundle these up in a single SQL file and run that against a restore of production.
Once your staging has cleared acceptance, you run the single SQL file again on the production machine.
I have used the Red Gate tools and they are great tools, but if you can't afford it, building the tools and working this way isn't too far from the ideal.
I'm using Subsonic's migrations mechanism so I just have a dll with classes in squential order that have 2 methods, up and down. There is a continuous integration/build script hook into nant, so that I can automate the upgrading of my database.
Its not the best thign in the world, but it beats writing DDL.
RedGate SqlCompare is a way to go in my opinion. We do DB deployment on a regular basis and since I started using that tool I have never looked back.
Very intuitive interface and saves a lot of time in the end.
The Pro version will take care of scripting for the source control integration as well.
I also maintain scripts for all my objects and data. For deploying I wrote this free utility - http://www.sqldart.com. It'll let you reorder your script files and will run the whole lot within a transaction.
I agree with keeping everything in source control and manually scripting all changes. Changes to the schema for a single release go into a script file created specifically for that release. All stored procs, views, etc should go into individual files and treated just like .cs or .aspx as far as source control goes. I use a powershell script to generate one big .sql file for updating the programmability stuff.
I don't like automating the application of schema changes, like new tables, new columns, etc. When doing a production release, I like to go through the change script command by command to make sure each one works as expected. There's nothing worse than running a big change script on production and getting errors because you forgot some little detail that didn't present itself in development.
I have also learned that indexes need to be treated just like code files and put into source control.
And you should definitely have more than 2 databases - dev and live. You should have a dev database that everybody uses for daily dev tasks. Then a staging database that mimics production and is used to do your integration testing. Then maybe a complete recent copy of production (restored from a full backup), if that is feasible, so your last round of installation testing goes against something that is as close to the real thing as possible.
I do all my database creation as DDL and then wrap that DDL into a schema maintainence class. I may do various things to create the DDL in the first place but fundamentally I do all the schema maint in code. This also means that if one needs to do non DDL things that don't map well to SQL you can write procedural logic and run it between lumps of DDL/DML.
My dbs then have a table which defines the current version so one can code a relatively straightforward set of tests:
Does the DB exist? If not create it.
Is the DB the current version? If not then run the methods, in sequence, that bring the schema up to date (you may want to prompt the user to confirm and - ideally - do backups at this point).
For a single user app I just run this in place, for a web app we currently to lock the user out if the versions don't match and have a stand alone schema maint app we run. For multi-user it will depend on the particular environment.
The advantage? Well I have a very high level of confidence that the schema for the apps that use this methodology is consistent across all instances of those applications. Its not perfect, there are issues, but it works...
There are some issues when developing in a team environment but that's more or less a given anyway!
Murph
I'm currently working the same thing to you. Not only deploying SQL Server databases from test to live but also include the whole process from Local -> Integration -> Test -> Production. So what can make me easily everyday is I do NAnt task with Red-Gate SQL Compare. I'm not working for RedGate but I have to say it is good choice.