Ok, so the problem is probably in my approach to liquibase, I have implemented some changes in the database side, and I want to create changesets, so I simply add a new sql file to my changesets. When I try to run luquibase update command I get error which tells me that some columns exist in the database.
For me is normal that before I create the changesets script I try to add columns in the database (i.e. using PhpMyAdmin). Then I want to share with this changes with other developers, so I generate sql (from my changes), adding this in the sql file and launching this file in changeset.
Can somebody tell me what I make wrong?
The problem concerns situation when I added some new columns to my mysql table, thenI created sql file whit alter_table script and thenI run liquibase update command.
Don't make manual updates in your database. All schema changes have to be done with liquibase or else - as in your case - your changesets will conflict with the existing schema.
While having all changes to your database be done with Liquibase before hand is ideal, there are certainly situations where that is not possible. One is the use case you've described. Another would be if a hotfix is applied to production and needs to be merged back to development.
If you are certain that your changeset has been applied to the environment, then consider running changelogSync. It will assert that all changesets have been applied and will update the Liquibase meta table with the appropriate information.
Although not ideal, we think that that changelogSync is required for real world applications where sometimes life does not progress as we would like. That's why we made certain to expose it clearly in Datical DB. We think it strikes a balance between reality and idealism.
Related
I need to create scripts for creating or updating a database. The scripts are created from my test Database or from my source control.
The script needs to upgrade a database from any version of my application to the current version so it needs to be agnostic to what already exists in the database.
I do not have access to the databases that will be upgraded.
e.g.
If a table does not exist the script should create it.
If the table exists the script should check if all the columns exist (And check their types).
I wrote a lot of this checking code in C# as in i have an SQL create table script and the C# code checks if the table (and columns) exists before running the script.
My code is not production ready and i wanted to know what ready made solutions are out there.
I have no experience with frameworks that can do this.
Such an inquiry is off-topic for SO anyway.
But depending on your demands, it may not be too hard to implement something yourself.
One straightforward approach would be to work with incremental schema changes; basically just a chronological list of SQL scripts.
Never change or delete existing script (unless something really bad is in there).
Instead, just keep adding upgrade scripts for every new version.
Yes, 15 years later you will have accumulated 5,000 scripts.
Trust me, it will be the least of your problems.
To create a new database, just execute the full chain of scripts in chronological order.
For upgrades, there are two possibilities.
Keep a progress list in every database.
That is basically just a table containing the names of all scripts that have already been executed there.
To upgrade, just execute every script that is not in that list already. Add them to the list as you go.
Note: if necessary, this can be done with one or more auto-generated, deployable, static T-SQL scripts.
Make every script itself responsible for recognizing whether or not it needs to do anything.
For example, a 'create table' script checks if the table already exists.
I would recommend a combination of the two:
option #1 for new versions (as it scales a lot better than #2)
option #2 for existing versions (as it may be hard to introduce #1 retroactively on legacy production databases)
Depending on how much effort you will put in your upgrade scripts, the 'option #2' part may be able to fix some schema issues in any given database.
In other words, make sure you start off with scripts that are capable of bringing messy legacy databases back in line with the schema dictated by your application.
Future scripts (the 'option #1' part) have less to worry about; they should trust the work done by those early scripts.
No, this approach is not resistant against outside interference, like a rogue sysadmin.
It will not magically fix a messed-up schema.
It's an illusion to think you can do that automatically, without somebody analyzing the problem.
Even if you have a tool that will recreate every missing column and table, that will not bring back the data that used to be in there.
And if you are not interested in recovering data, then you might as well discard (part of) the database and start from scratch.
On the other hand, I would recommend to make the upgrade scripts 'idempotent'.
Running it once or running it twice should make no difference.
For example, use DROP TABLE IF EXISTS rather than DROP TABLE; the latter will throw an exception when executed again.
That way, in desperate times you may still be able to repair a database semi-automatically, simply by re-running everything.
If you are talking about Schema state, you can look at state-based deployment-tools instead of change-based. (not the official terminology)
You should look at these two tools
SQL Server Data Tools (Dacpac) data-tier-applications which is practically free
RedGate has an entire toolset for this https://www.red-gate.com/solutions/need/automate. which is licensed
The one thing to keep in mind with State based deployments is that you don't control how the database gets from one-state to another, with SSDT
For example a column-rename = drop and recreate that column, same for a table-rename.
In their defence they do have some protections and do tell you what is about to happen.
EDIT (Updating to address comment below)
It should not be a problem that you can't access the TargetDb while in development. You can still use the above tools provided you can use them (Dacpac/Redgate) tooling when you are deploying to the TargetDb.
If you are hoping to have a dynamic TSQL script that can update a target database in an unknown state. Then that is a recipe for failure/disaster. I do have some suggestions at the end for dealing with this.
The way I see it working is
Do your development using Dacpac/Redgate
Build your artefacts Dacpac / Redgate package
Copy artefact to the deployment server with tools
when doing deployments use the tools (Dacpac Powershell) or Redgate manually
If your only choice is a TSQL script, then the only option is extensive-defensive coding covering all possibilities.
Every object must have an existence check
Every property must have a state check
Every object/property must have a roll forward / roll backward script.
For example to sync a table
A Script to check the table exists, if not create it
A script to check each property of the table is in the correct state
check all columns and their data-types and script to update them to match
check defaults
check indexes, partitioning etc
Even with this, you might not be able to handle every scenario.
The work you are trying to do requires you start using a standard change control process.
Given the risk of data loss, and issues related to creation of columns in a specific sequence and the potential for column definitions to change.
I recommend you look at defining a base line version which you will manually have to upgrade each system to.
You can roll your own code, and use a schema version table, or use any one of the tools available such as redgate sql source control, visual studio database projects, dbup, or others.
I do not believe any tool will bring you from 0-1, however, once you baseline, any one of these tools will greatly facilitate your workflow.
Start with this article Get Your Database Under Version Control
Here are some tools that can help you?
Octopus Schema Migrations
Flyway By Redgate
Idera Database Change Management
SQL Server Data Tools
In the scope of responsible programming and versioning, I would like to start to version my database changes especially since I am developing on my database instance then moving it to production. I haven't found any thing that truly makes sense to me on how to do this. I am using Visual Studio 2010 Pro as my IDE. Is there a document that makes this process simple and able to detect changes to the database with relative ease? Or what should I change in my workflow to make this easier?
One way that I've successfully done this sort of thing in the past, is via Sql Source Control. Visual Studio does not offer this functionality for you.
Alternatively, you can use SSMS to generate the Database scripts for you and save it as a file; then you can check in the script. You would chose whether you generate the whole DB script in one file or whether you do it on an object by object basis. The syncing part will have to be done by you by executing your scripts in production. In conclusion a total nightmare.
Redgate also offers Sql Compare, which is great for syncing databases. Take a look at their products if you or your company can afford them.
We use our own DB solution in-house which brings all the tools required for proper DB versioning. While I realize that it may not be a perfect solution for everyone, I invite you to have a look at it (it is open-source): bsn ModuleStore
The versioning aspect is as follows: the tool can script out the SQL semi-automatically, and it does reformat the source code to be in an uniform format. The files will therefore always be identical for the same source, no matter of when and by whom something has been scripted; this therefore works nicely with non-locking source control systems (especially SVN, Git or Mercurial).
The reformat puts all statements in the same form (e.g. optional keywords such as AS, INNER, OUTER etc. are dealt with), scripts everything to the "dbo" schema (even if it was in a different one), puts all identifiers into the square braces ([something]), uppercases all reserved words, does the indentation etc.
Besides versioning, the runtime part of the tool can diff the running DB and the CREATE scripts (DB source code) and apply updates automatically for all non-destructive changes (e.g. updating indexes, constraints, views, stored procedures, triggers, custom types, new tables etc.). Destructuve changes have to be scriped manually (table changes which then usually require data transformations). The runtime will make sure that all updates are performed in a transaction and rollback if the resulting DB doesn't match the CREATE scripts, therefore you get the safety of knowing that the DB is exactly on the version required by the application, even if it has been tampered with manually.
Also, multiple "modules" can be used in a single database. Each module is stored as a schema and independent of other schemas, thereby making it possible to add or remove modules from one single DB, and avoiding the need to create multiple databases for different parts of the application. Also, the use of schemas to do this makes sure that there are no name collisions.
It may be worth noting that the toolset has no dependency to the SMO, it is autonomous.
Save Your Database scripts at SVN. Here is the Refernce How to use SVN Tortoise
OR
Save your database script at VSS. Here is the reference What is VSS ? How can we use that ?
In both cases you can keep track of the changes done so that in future you can check the history which in saved in the form of versions.
You can use Red Gate product also
EDIT
How do you pull out what what has changed?
Use comparison feature to check the changes made in the previous versions.
How do I apply the changes to the live database server?
Download the latest file from server.
I hope you are not using the Drop statements for the Table in your consolidated script. As it will delete all records from the table.
Drop statements will take place for Stored Pro, View, Function etc.
Please note that you have to run the complete latest database script file on the production server with below mentioned action plans
1. Remove Drop Statement for Schema DDL
2. Add Drop/Create Statements for Stored Proc/Views
3. Include Alter statements DML of schema.
Hope this will definitely help you.
The more I use the DB Project, the less useful I find it. I'm trying to use this project type to manage my db schema and be able to use it to generate differences for test/production schema updates.
Right now I'm stuck trying to rename a column. I am using the object refactor tool, which updates the refactorlog, but that log seems to have no impact on the deployment of the sql file. Every time I deploy or diff it generates the sql as a column drop and add which purges all the existing data. You'd think the schema diff tool would have an option to map 2 columns as a rename, but that feature is conveniently missing.
Also, the Always re-create database option doesn't appear to do anything. Regardless of the state of this checkbox, my deployed sql is exactly the same. Which means each time I run it my database is re-created, which is contrary to what the document is telling me for unchecking this to run updates.
If the db project can't do a simple rename, then it's pretty much useless since I can't trust it to render the proper update sql (if and when I figure out how to prevent it from re-creating my database).
At this point I'm about to punt and just manage everything by hand, which I would prefer not to do, because contrary to my "useless" statement, the VS DB tools do some nice things, but 90% of the way there isn't good enough.
Has anyone else had experience dealing with these issues with a VS2010 DB Project who can talk me off the ledge?
VS 2010 Schema Compare does not use the refactor log. That is used only when doing a project deployment. Here is a definitive statement to that effect from the product manager:
http://social.msdn.microsoft.com/Forums/en/vstsdb/thread/fd2c3d02-8792-4d58-b1cb-0c804a1142de
We use SQL Server 2000/2005 and Vault or SVN on most of our projects. I haven't found a decent solution for capturing database schema/proc changes in either source control system.
Our current solution is quite cumbersome and difficult to enforce (script out the object you change and commit it to the database).
We have a lot of ideas of how to tackle this problem with some custom development, but I'd rather install an existing tool (paid tools are fine).
So: how do you track your database code changes? Do you have any recommended tools?
Edit:
Thanks for all the suggestions. Due to time constraints, I'd rather not roll my own here. And most of the suggestions have the flaw that they require the dev to follow some procedure.
Instead, an ideal solution would monitor the SQL Database for changes and commit any detected changes to SCM. For example, if SQL Server had an add-on that could record any DML change with the user that made the change, then commit the script of that object to SCM, I'd be thrilled.
We talked internally about two systems:
1. In SQL 2005, use object permissions to restrict you from altering an object until you did a "checkout". Then, the checkin procedure would script it into the SCM.
2. Run a scheduled job to detect any changes and commit them (anonymously) to SCM.
It'd be nice if I could skip the user-action part and have the system handle all this automatically.
Use Visual studio database edition to script out your database. Works like a charm and you can use any Source control system, of course best if it has VS plugins. This tool has also a number of other useful features. Check them out here in this great blog post
http://www.vitalygorn.com/blog/post/2008/01/Handling-Database-easily-with-Visual-Studio-2008.aspx
or check out MSDN for the official documentation
Tracking database changes directly from SSMS is possible using various 3rd party tools. ApexSQL Source Control automatically scripts any database object that is included in versioning. Commits cannot be automatically performed by the tool. Instead, the user needs to choose which changes will be committed.
When getting changes from a repository, ApexSQL Source Control is aware of a SQL database referential integrity. Thus, it will create a synchronization scripts including all dependent objects that will be wrapped in a transactions so, either all changes will be applied in case no error is encountered, or none of the selected changes is applied. In any case, database integrity remains unaffected.
I have to say I think a visual studio database project is also a reasonable solution to the source control dilemma. If it's set up correctly you can run the scripts against the database from the IDE. If your script is old, get the latest, run it against the DB. Have a script that recreates all the objects as well if you need, new objects must be added to the this script as well by hand, but only once
I like every table, proc and function to be in it's own file.
One poor man's solution would be to add a pre-commit hook script that dumps out the latest db schema into a file and have that file committed to your SVN repository along with your code. Then, you can diff the db schema files from any revision.
I just commit the SQL-alter-Statement additional to the complete SQL-CreateDB-statement.
Rolling your own from scratch would not be very doable, but if you use a sql comparison tool like Redgate SQL Compare SDK to generate your change files for you it would not take very long to half-roll what you want and then just check those files into source control. I rolled something similar for myself to update changes from our development systems to our live systems in just a few hours.
In our environment, we never change the DB manually: all changes are done by scripts at release time, and the scripts are kept in the version control system. One important part of this procedure is to be sure that all scripts can be run again against the same DB the scripts are idempotent?) without loss of data. For example, if you add a column, make sure that you do nothing if the column is already there.
Your comment about "suggestions have the flaw that they require the dev to follow some procedure" is really a tell-tale. It's not a flaw, it's a feature. Version control helps developers in following procedures and makes the procedures less painful. If you don't want to follow procedures, you don't need version control.
In SQL2000 generate each object into it's own file, then check them all into your source control. Let your source control handle the change history.
In SQL 2005, you'll need to write a bit of code to generate all objects into separate files.
In one project I arranged by careful attention in the design that all the important data in the database can be automatically recreated from external places. At startup the application creates the database if it is missing, and populates it from external data sources, using a schema in the application source code (and hence versioned with the application). The database store name (a sqlite filename although most database managers allow multiple databases) includes a schema version, and we increase the schema version whenever we commit a schema change. This means when we restart the application to a new version with a different schema that a new database store is automatically created and populated. Should we have to revert a deployment to an old schema then the new run of the old version will be using the old database store, so we get to do fast downgrades in the event of trouble.
Essentially, the database acts like a traditional application heap, with the advantages of persistence, transaction safety, static typing (handy since we use Python) and uniqueness constraints. However, we don't worry at all about deleting the database and starting over, and people know that if they try some manual hack in the database then it will get reverted on the next deployment, much like hacks of a process state will get reverted on the next restart.
We don't need any migration scripts since we just switch database filename and restart the application and it rebuilds itself. It helps that the application instances are sharded to use one database per client. It also reduces the need for database backups.
This approach won't work if your database build from the external sources takes longer than you will allow the application to be remain down.
If you are using .Net and like the approach Rails takes with Migrations, then I would recommend Migrator.Net.
I found a nice tutorial that walks through setting it up in Visual Studio. He also provides a sample project to reference.
We developed a custom tool that updates our databases. The database schema is stored in a database-neutral XML file which is then read and processed by the tool. The schema gets stored in SVN, and we add appropriate commentary to show what was changed. It works pretty well for us.
While this kind of solution is definitely overkill for most projects, it certainly makes life easier at times.
Our dbas periodically check prod against what is in SVN and delete any objects not under source control. It only takes once before the devlopers never forget to put something in source control again.
We also do not allow anyone to move objects to prod without a script as our devs do not have prod rights this is easy to enforce.
In order to track all the change like insert update and delete there will be a lot of overhead for the SVN.
It is better to track only the ddl changes like (alter, drop, create) which changes the schema.
You can do this Schema tracking easily by creating a table and a trgger to insert data to that table.
Any time you want u can get the change status by querying from that table
There are a lots of example here and here
I'm looking for some "Best Practices" for automating the deployment of Stored Procedures/Views/Functions/Table changes from source control. I'm using StarTeam & ANT so the labeling is taken care of; what I am looking for is how some of you have approached automating the pull of these objects from source - not necessarily StarTeam.
I'd like to end up with one script that can then be executed, checked in, and labeled.
I'm NOT asking for anyone to write that - just some ideas or approaches that have (or haven't) worked in the past.
I'm trying to clean up a mess and want to make sure I get this as close to "right" as I can.
We are storing the tables/views/functions etc. in individual files in StarTeam and our DB is SQL 2K5.
We use SQL Compare from redgate (http://www.red-gate.com/).
We have a production database, a development database and each developer has their own database.
The development database is synchronised with the changes a developer has made to their database when they check in their changes.
The developer also checks in a synchronisation script and a comparison report generated by SQL Compare.
When we deploy our application we simply synchronise the development database with the production database using SQL Compare.
This works for us because our application is for in-house use only. If this isn't your scenario then I would look at SQL Packager (also from redgate).
I prefer to separate views, procedures, and triggers (objects that can be re-created at will) from tables. For views, procedures, and triggers, just write a job that will check them out and re-create the latest.
For tables, I prefer to have a database version table with one row. Use that table to determine what new updates have not been applied. Then each update is applied and the version number is updated. If an update fails, you have only that update to check and you can re-run know that the earlier updates will not happen again.