The theme of today’s release can be summed up in one word: variables, variables and more variables!
SQLCMD Variable Support Added
If in your organisation you need handle subtle differences in the setup of your environments (eg. Test/Staging/Production), or if you are deploying to customer sites with variations that you don’t want to hardcode into your project scripts, it can be useful to provide certain values from an external source. ReadyRoll 1.4 allows you to do this by tapping into the SQLCMD variable support built-in to Visual Studio, providing you with a way to write scripts that use different values depending on the context.
When working within Visual Studio, you can use sandbox or project-level, and outside the IDE you can provide environment-level values from an external source, like a Continuous Integration/Automated Deployment server (eg. Octopus).
Project and Sandbox-specific values
Start by adding a variable to the SQLCMD Variables tab in the Project Property pages. The value you provide in the Default column will be stored in the project file (and therefore shared with other team members) however the Local value is specific to your machine (stored in the non-source controlled .user file). If you leave the Local column blank, the Default will be used when deploying inside Visual Studio.
Using the $(VariableName) notation, reference the variable you just created in a new Deploy-Once script.
When you build the project, the variable will be substituted with the Default value (or Local value, if it was provided).
When deploying your database outside of Visual Studio, you can also provide a set of values for the variables defined in your project.To do this, first enable SQLCMD package scripts for output (or enable .nupkg output if you are using Octopus).
Build your project to produce the package deployment script, eg. MyDatabase_Package.sql. Notice in the header of the file that the full list of project variables are included, but commented out along with their default values. You will need to provide values for each of the variables listed, as part of the next step to deploy your database (Note that $(DatabaseName) is a built-in SQLCMD variable that is required for all database projects).
To deploy your database, open the command prompt and execute the following command:
SQLCMD.EXE -E -S "(localdb)\Projects" -i "AdventureWorks_Package.sql" -v DatabaseName=AdventureWorks_STAGING -v Environment=STAGING
Note: There is currently no straightforward way of passing SQLCMD variables into MSBuild; at present the Package deployment method is the best way to use SQLCMD variables at this time. If you’d prefer to use the Patch deployment script method instead (which provides a delta file of pending migrations and is only available via MSBuild), please get in touch.
Next we’ll look at a variation of this approach, which involves using the built-in Octopus support to provide SQLCMD variable values you can use in your database deployments.
Enhanced Octopus Support with Variable Mapping
ReadyRoll 1.3.4 introduced support for Octopus, making it easy for database deployments to be coordinated alongside other application components using the NuGet-based package format.
ReadyRoll 1.4 builds on this support by providing automated mapping of Octopus variables to SQLCMD variables. This makes it incredibly easy to consume values from your existing pool of environment-specific variables, or to make use of the project and package variables provided by Octopus itself.
For example, say you wanted to store the version number of the deployment package in the target database. To do this, firstly add the $(OctopusPackageVersion) variable to the ReadyRoll project and give it a Default value, eg. 188.8.131.52.
Then include a reference to the variable in a Deploy-Once script. When you deploy locally it will output the Default value, however when you deploy via Octopus the value will be substituted with the deployment package version:
To get a full list of built-in variables, check out the Octopus Variables documentation.
Mapping isn’t just limited to built-in Octopus variables; simply add your variables to your ReadyRoll project to map your custom variables as well.
Note: If you’re already deploying your database projects using Octopus, please note there is a code-breaking change in this release: previously, the $(DatabaseName) SQLCMD variable would to hardcoded to the name specified in your ReadyRoll project. From ReadyRoll 1.4 onwards, you will need to provide a value for the database name within the Octopus project variables.
As ReadyRoll projects are based within the Visual Studio IDE, you’ve always had the ability to develop and deploy multiple databases. However up until now, it has been difficult to manage the deployment of databases with interdependent object references. For example, say you have two projects: DatabaseA and DatabaseB. If DatabaseB contained a script that referred to an object within DatabaseA, you would first need to build and deploy DatabaseA before you could even build DatabaseB. This is because of the way that ReadyRoll uses a separate copy of your database called the Shadow that ensures your project scripts are parsed & validated before deploying to your Sandbox database. This process is called gated deployment, and it requires that all database references be dynamic (which is why you need to use the $(DatabaseName) variable whenever you reference your database).
To make it easier to work with interdependent databases, ReadyRoll 1.4 introduces the ability to create dynamic database references within your projects.
Start by adding a Database Reference to your project (from the Solution Explorer context menu).
Don’t worry about the Database name field; this will be automatically substituted at build time.
To refer to an object within the database, you can then use a three-part object name within a Deploy-Once script using — you guessed it — a SQLCMD variable:
When deploying outside Visual Studio, just make sure you specify a variable/value pair for each of the database names that are referenced from your project.
Object Exclusion Rules
For a variety of reasons, sometimes it’s necessary to exclude certain objects from your database projects: maybe some objects are needed only in Production (such as log tables or reporting objects) or perhaps their deployment is managed by a completely separate deployment mechanism (like in a CRM system). This can be a problem when using the ReadyRoll DBSync tool, which will eagerly import any new objects from the source database that are added to your schemas.
To make it easier to prevent these types of objects from appearing in your project altogether, ReadyRoll 1.4 introduces regex-based exclude rules to the project system. For example, say you wanted to exclude the [reporting].[log] table object from the database. To do so, just add the following to the top of your .sqlproj file:
<PropertyGroup> <ExcludeObjectsFromImport> Table=\[reporting\]\.\[log\]; </ExcludeObjectsFromImport> </PropertyGroup>
If you’d like to exclude all Tables & Stored Procedures in a particular Schema (along with the Schema itself) from your project, try this:
<PropertyGroup> <ExcludeObjectsFromImport> Schema=\[reporting\]; Table=\[reporting\]\.\[(.*?)\]; StoredProcedure=\[reporting\]\.\[(.*?)\]; </ExcludeObjectsFromImport> </PropertyGroup>
Don’t worry… we won’t be offended if you add lots of exclude rules to your project! Thanks to @DataChomp for the idea.
Head to the ReadyRoll website to grab Version 1.4 now!