I have a few stored procedures that will only be used for maintenance operations (facilitating truncation of tables, rebuilding indexes etc). In my opinion, the most logical location for these would be the master database (or another central database), so that other databases could share this functionality.
This would further clarify the intent of these procedures and exclude them from DACPAC deployments. However, cross-database queries are not permitted in Azure SQL, and I cannot find a natural location to place these procedures.
Where would you place these types of stored procedures that are not essential to the operation of the business?
Here's a link that may help you.
Create stored procedures in Azure SQL database - DatabaseFAQs.com