My organization is planning to adopt SQL Server 2012 AlwaysOn and I am trying to understand what impact (if any) it will have on our application upgrade process.
We release application updates on an 8 week cycle and any release could include schema changes and/or data migrations.
What I am trying to understand is whether or not the AlwaysOn HA/DR solution handles the schema changes transparently (new columns, indexes get added to secondaries) or is manual intervention required to create the schema on each instance and then turn Always On back on.
The data migration piece I'm assuming is handled transparently but would like to confirm that as well.
I guess I am also making a blanket assumption that there is no difference in these behaviors based on the AlwaysOn configuration which may be false as well. Please let me know.
In a nutshell; In any given release of my application I may change a very large table (10s to 100s of millions of records) by adding columns to it. Some columns may be "net new" so they can make use of the Enterprise Online schema change functionality. Other columns may be a refactoring of an existing column (FullName gets split into FirstName and LastName) and a migration will be run for each row in the table to populate these fields. Do any of these behaviors require DBAs to change the AlwaysOn configuration or is this handled by default and all secondaries get the DDL and DML statements "for free"?
Thanks for any clarity you can provide.