@dpaisig Thank you for reaching out.
Resource groups help you organize your resources better. Think of them as a logical grouping for Azure Resources.
They don't restrict connectivity between resources.
Can Azure SQL 1 see/do queries in Azure SQL 2?
Yes, you can use Elastic queries to run query across Azure SQL Databases.
Can Web App 1 call database Azure SQL 2?
Yes, Web apps connect to the database using a connection string. A tutorial is here
You can connect to the database even if they are not in the same resource group.
You can have your different webapps in different resource groups, but they can all share a database in another resource group.
Please let us know if you have further questions.
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