What is the best way to execute long-running and high memory usage tasks on Azure?

I need to find the best way to preform long running tasks on Azure. Scenario:

1. User picks the dataset and filters on the web app (Azure App Service)
2. Based on the requirements we create SQL query
3. Query is executed against one or more Azure SQL databases
4. Data is being exported in .csv format and uploaded to Azure Blob Storage

The main issues are that execution of some SQL queries can last for 2+ hours and resultset can have 100M+ rows.

I believe that Azure Functions (and subsequently Durable Functions) are not a option because of the timeout and memory usage.

I believe that Azure Functions (and subsequently Durable Functions) are not a option because of the timeout and memory usage.

Timeout limit is only in consumption plan. If you want to get rid of timeout limit and want more memory, you can use premium plan or app service plan. And because azure function can scale out horizontally, you can split the result to multiple and then input the azure function.

And also, you can use web jobs.