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I have been developing against SQL Server 2012 Enterprise, and came to migrate to production, where I found our hosting provider had installed Standard. I didn't think it should be a problem, as I hadn't implemented any enterprise specific features. However when I restored the DB it failed to activate, and in the Event Log, I found a message indicating the database couldn't be activated because it contained features not supported by the version. When I dug deeper, I found that it appeared that FTS or some other function had automatically created 5 partition functions and schemes.
I then went through a time consuming process to remove the partitions functions and schemes, and could successfully restore the database on the Standard edition.
After a while I backed up the DB (with no PFs or PSs), transferred it to my dev env, restored it (on SQL Enterprise), and after some time I found that a single partition function and scheme had been created. When I next came to backup and restore to prod, this time the database activated ok without error - even though there were partition functions and schemes.
I have just run the following:
SELECT feature_name FROM sys.dm_db_persisted_sku_features ;
from here
http://msdn.microsoft.com/en-us/library/cc280724.aspx
and found that for the db with 5 partitions functions/schemes, Partitioning is listed as a version specific feature. When running the same against the db with 1 function/scheme, it's not listed.
Is there something going on here that Auto created, FTS related partition schemes are ok on standard edition, but not manually created/other types? (keep in mind I never manually implemented partitioning)
Based on MSDN article Features Supported by the Editions of SQL Server 2012:
Only Enterprise version supports Partitioning of tables and indexes. It means that if any table or index is partitioned, then it cannot be imported into any other version. However a partition scheme and partition finction can exist without being used by any table or index. In this case import succeeds, as there are no partitioned tables or indexes.
Moreover, the RDBMS Managebility section tells, that Distributed partitioned views are supported by all versions to some extent. Thus permitting partition schemes and functions to exist as definition in all versions.
I am working on a project which uses a relational database (SQL Server 2008). The local (on-premises) application both reads and writes to the database. I am working on a different front end for Azure (MVC2 Web Role), which will use the same data, but in a read only fashion. If I was deploying a traditional web app, I would use SQL Express to act as the local database, and deploy changes with updates to the application (the data changes very slowly) or via some sync system.
With Azure, the picture is a little cloudy (sorry, I had to). I can't seem to find any information to indicate if SQL Express will work inside of Web Roles, and if so, how to do it. Does anyone know if using SQL Express in an Azure web role is possible?
Other options I could do if forced: SQL CE or use SQL Azure. Both have a number of downsides, and are definitely less than perfect.
Thanks,
Erick
Edit
I think my scenario may not have been clear enough.
This data won't change between deployments, and is only accessed from within the Web Role; it is basically a static cache. The on-premises part is kind of a red herring, as it doesn't impact the data on the web role (aside from being its source). Basically, what I want to do is have a local data store/cache that I use existing T-SQL/DAL code with.
While I could use SQL Azure, it doesn't add anything, and if anything only adds additional overhead and failure points. I could also use a VM Role, but that is way too costly/complex.
In a perfect world, I would package the MDF into the cspkg (so it gets deployed with the app) and then use it locally from within the role. If there is no way to do this, then that is ok and I need to figure out the pros and cons of other solutions. We don't live in a perfect world. :)
You might be able to run SQL Express using a custom VHD but you won't be able to rely on any data every being present on that VHD. The VMs are completely reset when they reboot - there is no physical persistence across reboots.
If you wanted to, you might be able to locate your entire SQL Server installation in Azure blob storage.
However, in doing all of this, you'll only be able to have one worker/web role that can use that database. Remember: a SQL Server database can only be attached to one SQL Server at a time. If you want to scale out, you'll have to create new SQL Server instances for every web/worker role.
Outside of cost concerns, I can't think of anything that is in SQL Express that should be a show stopper for 99.9% of applications out there.
Adding to Jeremiah's answer: SQL Azure should give you nearly everything SQL Express does today, and you can use the Sync service to synchronize on-premise SQL Server with SQL Azure.
If you installed SQL Express into a VM role, you'd be consuming around $90 monthly just for that instance, plus blob storage (you'd want a Cloud Drive for durability). By definition, a VM Role (or any role) must support scale-out; if you were to scale to 2 instances for whatever reason, both instances would need their own copy of the database, so you'd need to create a blob snapshot for each instance.
Keep in mind, though, if you choose to install SQL Express in a VM: once you're at 2 instances, along with, say, 20GB per instance of blob storage, you're nearing $200 monthly and you're maintaining your VM's OS patches, SQL Express configuration and updates, failure recovery procedures, etc. In contrast, SQL Azure at 20GB, while costing the same $200, will offer better performance and works with the sync service, while completely removing any OS or database server management tasks from you.
To add to the already existing answers and for anyone wondering if its a good idea to run SQL Express in the cloud:
it does makes sense as a temporary storage area. Consider this architectural approach:
say you're spinning up nodes to run jobs. Storing a gazillion of calculation results might be a good idea inside a local SQL Express for each node, and provide the aggregated responses immediately when the job finishes on the node. Transfer of the no longer hot results to off-prem SQL server for future reporting/etc can be done afterwords. SQL Azure may not be optimal from the volume/latency/cost perspective to store gazillion of results and ATS will not always fit the bill, especially when relational data, performance or existing code are involved.
To expand on what David mentioned you can register for SQL Azure Data Sync CTP2 that would allow sync from SQL Server to SQL Azure here: http://www.microsoft.com/en-us/SQLAzure/datasync.aspx
Make sure to use CTP2 though since CTP1 did not support SQL Server.
If it's a read only local cache - SQL CE 4 or SQLite.
Both have Entity Framework providers.
If you're writing to it - SQL Azure
The Background
My group has 4 SQL Server Databases:
Production
UAT
Test
Dev
I work in the Dev environment. When the time comes to promote the objects I've been working on (tables, views, functions, stored procs) I make a request of my manager, who promotes to Test. After testing, she submits a request to an Admin who promotes to UAT. After successful user testing, the same Admin promotes to Production.
The Problem
The entire process is awkward for a few reasons.
Each person must manually track their changes. If I update, add, remove any objects I need to track them so that my promotion request contains everything I've done. In theory, if I miss something testing or UAT should catch it, but this isn't certain and it's a waste of the tester's time, anyway.
Lots of changes I make are iterative and done in a GUI, which means there's no record of what changes I made, only the end result (at least as far as I know).
We're in the fairly early stages of building out a data mart, so the majority of the changes made, at least count-wise, are minor things: changing the data type for a column, altering the names of tables as we crystallize what they'll be used for, tweaking functions and stored procs, etc.
The Question
People have been doing this kind of work for decades, so I imagine there have got to be a much better way to manage the process. What I would love is if I could run a diff between two databases to see how the structure was different, use that diff to generate a change script, use that change script as my promotion request. Is this possible? If not, are there any other ways to organize this process?
For the record, we're a 100% Microsoft shop, just now updating everything to SQL Server 2008, so any tools available in that package would be fair game.
I should clarify I'm not necessarily looking for diff tools. If that's the best way to sync our environments then it's fine, but if there's a better way I'm looking for that.
An example doing what I want really well are migrations in Ruby on Rails. Dead simple syntax, all changes are well documented automatically and by default, determining what migrations need to run is almost trivially easy. I'd love if there was something similar to this for SQL Server.
My ideal solution is 1) easy and 2) hard to mess up. Rails Migrations are both; everything I've done so far on SQL Server is neither.
Within our team, we handle database changes like this:
We (re-)generate a script which creates the complete database and check it into version control together with the other changes. We have 4 files: tables, user defined functions and views, stored procedures, and permissions. This is completely automated - only a double-click is needed to generate the script.
If a developer has to make changes to the database, she does so on her local db.
For every change, we create update scripts. Those are easy to create: The developer regenerates the db script of his local db. All the changes are now easy to identify thanks to version control. Most changes (new tables, new views etc) can simply be copied to the update script, other changes (adding columns for example) need to be created manually.
The update script is tested either on our common dev database, or by rolling back the local db to the last backup - which was created before starting to change the database. If it passes, it's time to commit the changes.
The update scripts follow a naming convention so everybody knows in which order to execute them.
This works fairly well for us, but still needs some coordination if several developers modify heavily the same tables and views. This doesn't happen often though.
The important points are:
database structure is only modified by scripts, except for the local developer's db. This is important.
SQL scripts are versioned by source control - the db can be created as it was at any point in the past
database backups are created regularly - at least before making changes to the db
changes to the db can be done quickly - because the scripts for those changes are created relatively easily.
However, if you have a lot of long lasting development branches for your projects, this may not work well.
It is by far not a perfect solution, and some special precautions are to be taken. For example, if there are updates which may fail depending on the data present in a database, the update should be tested on a copy of the production database.
In contrast to rails migrations, we do not create scripts to reverse the changes of an update. But this isn't always possible anyway, at least in respect to the data (the content of a dropped column is lost even if you recreate the column).
Version Control and your Database
The root of all things evil is making changes in the UI. SSMS is a DBA tool, not a developer one. Developers must use scripts to do any sort of changes to the database model/schema. Versioning your metadata and having upgrade script from every version N to version N+1 is the only way that is proven to work reliably. It is the solution SQL Server itself deploys to keep track of metadata changes (resource db changes).
Comparison tools like SQL Compare or vsdbcmd and .dbschema files from VS Database projects are just last resorts for shops that fail to do a proper versioned approach. They work in simple scenarios, but I see them all fail spectacularly in serious deployments. One just does not trust a tool to do a change to +5TB table if the tools tries to copy the data...
RedGate sells SQL Compare, an excellent tool to generate change scripts.
Visual Studio also has editions which support database compares. This was formerly called Database Edition.
Where I work, we abolished the Dev/Test/UAT/Prod separation long ago in favor of a very quick release cycle. If we put something broken in production, we will fix it quickly. Our customers are certainly happier, but in the risk avert corporate enterprise, it can be a hard sell.
There are several tools available for you. One is from Red-Gate called SQL Compare. Awesome and highly recommended. SQL Compare will let you do a diff in schemas between two databases and even build the sql change scripts for you.
Note they have been working on a SQL Server source control product for awhile now as well.
Another (if you're a visual studio shop) is the schema and data compare features that is part of Visual Studio (not sure which versions).
Agree that SQL Compare is an amazing tool.
However, we do not make any changes to the database structure or objects that are not scripted and saved in source control just like all other code. Then you know exactly what belongs in the version you are promoting because you have the scripts for that particular version.
It is a bad idea anyway to make structural changes through the GUI. If you havea lot of data, it is far slower than using alter table at least in SQL Server. You only want to use tested scripts to make changes to prod as well.
I agree with the comments made by marapet, where each change must be scripted.
The problem that you may be experiencing, however, is creating, testing and tracking these scripts.
Have a look at the patching engine used in DBSourceTools.
http://dbsourcetools.codeplex.com
It's been specifically designed to help developers get SQL server databases under source-code control.
This tool will allow you to baseline your database at a specific point, and create a named version (v1).
Then, create a deployment target - and increment the named version to v2.
Add patch scripts to the Patches directory for any changes to schema or data.
Finally, check the database and all patches into source-code control, to distribute with devs.
What this gives you is a repeatable process to test all patches to be applied from v1 to v2.
DBSourceTools also has functionality to help you create these scripts, i.e. schema compare or script data tools.
Once you are done, simply send all of the files in the patches directory to your DBA to upgrade from v1 to v2.
Have fun.
Another "Diff" tool for databases:
http://www.xsqlsoftware.com/Product/Sql_Data_Compare.aspx
Keep database version in a versioning table
Keep script file name that was successfully applied
Keep md5 sum of each sql script that has been applied. It should ignore spaces when calculate md5 sum. Must be effective.
Keep info about who applied a script Keep info about when a script was applied
Database should be verified on application start-up
New sql script should be applied automatically
If md5 sum of a script that was already applied is changed, error should be thrown (in a production mode)
When script have been released it must not be changed. It must be
immutable in a production environment.
Script should be written in a way, so it could be applied to different types of database (see liquibase)
Since most ddl statements are auto-committing on most databases, it is best to have a single ddl statement per SQL script.
DDL sql statement should be run in a way, so it can be executed several times without errors. Really helps in a dev mode, when you may edit script several times. For instance, create a new table, only if it does not exist, or even drop table before creating a new one. It will help you in a dev mode, with a script that has not been released, change it, clear md5 sum for this script, rerun it again.
Each sql script should be run in its own transaction.
Triggers/procedures should be dropped and created after each db
update.
Sql script is kept in a versioning system like svn
Name of a script contains date when it was committed, existing (jira) issue id, small description
Avoid adding rollback functionality in scripts (liquibase allow to do that). It makes them more complicated to write and support. If you use exactly one ddl statement per script, and dml statements are run within a
transaction, even failing a script will not be a big trouble to
resolve it
This is the workflow we have been using succesfully:
Development instance: SQL objects are created/updated/deleted in DB using MSSQL Studio and all operations are saved to scritps we include in each version of our code.
Moving to production: We compare schema between dev and prod db using SQL Schema Compare in Microsoft Visual Studio. We update prod using the same tool.
I have two databases: the source is a database from SQL Server Express by client and the target is a database from SQL Server 2005 database as backup initially. What I need is to sync the source to the target db if there is any difference between them and the sync is one-way from source to target.
I am not sure what tools are available. I tried to google this issue and found MS VS Team Edition (2005) has a tool to sync database, which can generate T-SQL scripts as well. Not sure if this one is good or not. Can I use the script as a scheduled job on SQL Server (target server)? By the way, I don't have Team Edition right now but I do have VS 2005 Prof. Any suggestions?
IMHO by far the easiest and fastest way to sync the two databases one-way (A to B) is to backup database on A and restore it on B. This could be done via T-SQL, let me know if you would like me to post SQL statements
Ideally you would set up Transactional Replication from your source to your target(s). However, since your source is Express edition and Replication does not work with Express as a publisher (source) but only as a subscriber (target), you cannot use it.
The best solution would be to upgrade your Express edition to SKU that supports Replication publishing (ie. Standard Edition).
Log shipping, or manual backup/restore, will not work because it will create an absolutely identical copy of the source db at the target, overwritting any changes made by the target (you mention 'some differences' may exist). Same goes for File/Copy.
SQL Compare tools are OK for a one time manual operation, but they fail at automated operations because they always compare the two databases from scratch, ei. are not capable of synching just what changed. As soon as data grows to a sufficient size, the comparison approach is doomed as it has to ship over the entire database for purpose of comparison alone.
Other solutions are to set up pro-active real-time ETL, but the time/cost investment into this is prohibitive compared with the cost of a SE license and deploying Replication.
Pay to play:
http://www.red-gate.com/products/SQL_Compare/index.htm
Free, open source:
http://www.codeplex.com/OpenDBiff
You should into the SQL Server tools produced by Red-Gate. I've found them to be the best around.
If you have SQL Server 05, you can use replication services(this comes with SQL Server). If you open up your management studio, under your server folders you should see one titled "Replication". From here you can setup subscriptions or publications with push or pull syncs.
Here's MSDN's take: http://msdn.microsoft.com/en-us/library/ms151198.aspx
If this is a one time / once-in-a-while thing, you can use SnapShot Replication.
If you need the databases to be in sync all the time, you can use Transactional Replication.
http://msdn.microsoft.com/en-us/library/ms151847.aspx
In addition to Red Gate tools you can try DB Ghost as well http://www.innovartis.co.uk/. It's most useful as a automated build tool, but does also have an user interface to diff and sync databases. It costs ~$350.00
USing microsoft sync framerok
http://msdn.microsoft.com/en-us/library/ee819079.aspx
http://msdn.microsoft.com/en-us/library/ff928525.aspx
We have 18 databases that should have identical schemas, but don't. In certain scenarios, a table was added to one, but not the rest. Or, certain stored procedures were required in a handful of databases, but not the others. Or, our DBA forgot to run a script to add views on all of the databases.
What is the best way to keep database schemas in sync?
For legacy fixes/cleanup, there are tools, like SQLCompare, that can generate scripts to sync databases.
For .NET shops running SQL Server, there is also the Visual Studio Database Edition, which can create change scripts for schema changes that can be checked into source control, and automatically built using your CI/build process.
SQL Compare by Red Gate is a great tool for this.
SQLCompare is the best tool that I have used for finding differences between databases and getting them synced.
To keep the databases synced up, you need to have several things in place:
1) You need policies about who can make changes to production. Generally this should only be the DBA (DBA team for larger orgs) and 1 or 2 backaps. The backups should only make changes when the DBA is out, or in an emergency. The backups should NOT be deploying on a regular basis. Set Database rights according to this policy.
2) A process and tools to manage deployment requests. Ideally you will have a development environment, a test environment, and a production environment. Developers should do initial development in the dev environment, and have changes pushed to test and production as appropriate. You will need some way of letting the DBA know when to push changes. I would NOT recommend a process where you holler to the next cube. Large orgs may have a change control committee and changes only get made once a month. Smaller companies may just have the developer request testing, and after testing is passed a request for deployment to production. One smaller company I worked for used Problem Tracker for these requests.
Use whatever works in your situation and budget, just have a process, and have tools that work for that process.
3) You said that sometimes objects only need to go to a handful of databases. With only 18 databases, probably on one server, I would recommend making each Databse match objects exactly. Only 5 DBs need usp_DoSomething? So what? Put it in every databse. This will be much easier to manage. We did it this way on a 6 server system with around 250-300 DBs. There were exceptions, but they were grouped. Databases on server C got this extra set of objects. Databases on Server L got this other set.
4) You said that sometimes the DBA forgets to deploy change scripts to all the DBs. This tells me that s/he needs tools for deploying changes. S/He is probably taking a SQL script, opening it in in Query Analyzer or Manegement Studio (or whatever you use) and manually going to each database and executing the SQL. This is not a good long term (or short term) solution. Red Gate (makers of SQLCompare above) have many great tools. MultiScript looks like it may work for deployment purposes. I worked with a DBA that wrote is own tool in SQL Server 2000 using O-SQl. It would take an SQL file and execute it on each database on the server. He had to execute it on each server, but it beat executing on each DB. I also helped write a VB.net tool that would do the same thing, except it would also go through a list of server, so it only had to be executed once.
5) Source Control. My current team doesn't use source control, and I don't have enough time to tell you how many problems this causes. If you don't have some kind of source control system, get one.
I haven't got enough reputation to comment on the above answer but the pro version of SQL Compare has a scriptable API. Given that you have to replicate stuff to all of these databases you could use this to make an automated job to either generate the change scripts or to validate that the databases are all in sync. It's also not much more expensive than the standard version.
Aside from using database comparison tools, with 18 databases you should have a DBA, so enforce a policy that only the DBA can change tables at the database level by restricting access to CREATE and ALTER to the DBA only. On both your test and live databases. The dev database shouldn't have this, of course! Make the developers who have been creating or altering the schemas willy-nilly go via the DBA.
Create a single source-controlled DDL/SQL script for each release and only use it to update the databases. The diff tools can be useful but mainly for checking that you haven't made a mistake and getting out of trouble when the policies fail. Combine the DDL, SQL, and stored procedure scripts into a single script so that it's not easy to "forget" to run one of the scripts.
We have got a tool called DB Schema Difftective that can compare and sync database schemas. With our other tool, DB MultiRun you can easily deploy generated (sync) scripts to multiple db servers (project based).
I realize this post is old, but TurnKey is correct. If you are a developer working in a team environment, the best way to maintain a database schema for a large application, is to make updates to a Master Schema in what ever source safe you use. Simply write your own Scripting class and your Database will be perfect every time.