FluentMigrator和Azure部署

Question

I have a new ASP.NET MVC project that will be hosted in Azure using their Cloud Services with multiple web roles running. My question is about how to do production deployments using FluentMigrator to do the database changes.

If I run FluentMigrator during my TeamCity deployment it seems that it would update the database first and then would do deployments to the multiple web roles one at a time. Therefore, it seems that some users would be accessing the old version of the site and using the new database structure which will lead to mismatches and exceptions being thrown.

What are best practices/suggestions for doing deployments to a production Azure SQL Database environment using FluentMigrator?

Answer 1

First off, make sure you deploy to the staging slot and only do a VIP swap once you are happy everything is working fine.

If your migrations include things like adding columns, indexes and tables - these will be non-breaking changes and your old code should work just fine against the new database.

If your migrations include breaking changes though (changing column names, dropping columns, changing columns datatypes) then you should put up a holding page while you deploy. We have a flag we set in the config file that serves a holding page while we are doing these type of deployments.