The purpose of an Elastic Job is to execute a T-SQL script that is scheduled or executed ad-hoc against a group of Azure SQL databases. Targets can be in different SQL Database servers, subscriptions, and/or regions. This blog post is quite long and heavy (code wise) so grab a coffee and follow through.
The architecture you could follow is shown below.
There are a few ways to scale a SQL elastic pool. For this blog post I show you how to scale up. It can be done via the Azure portal and Azure PowerShell but not T-SQL.
I would say the PowerShell route is the easiest. Connect to your account and issue the below code. Here I am going from a 100 edtu pool to a massive 2000 edtu pool whilst tweaking the min/max setting.
I use elastic pools. They are a fabulous way of saving money when running many Azure SQL Databases, that is assuming you understand the resource utilization patterns of the databases involved.