What is the best way to display detailed error messages in Azure Data Factories?
1: Create a log workspace, configure Data Factories to send logs there, query it every 5 minutes using alerts, and trigger an action group through a webhook in a Logic App when the query returns a row. In the alert, I include dimensions for each column, such as start, end, and status. I then extract these dimensions from the JSON and transform them into a message in Slack.
2: Set up a 5-minute recurrence in a Logic App. Each time, query the logs with a condition "time generated >= ago(5m)." If it returns rows, post the information in Slack; otherwise, stop the execution.
Which approach would be more efficient and cost-effective?
Integrating log analytics or application insights in alert generation is how its intended as the primary purpose, as you figured out there can be many ways of doing one thing. You can also trigger the logic app from your data factory (to be run every 5 mins as scheduled). I dont think there will be much of a cost difference between any of the solutions, as you are not spending much compute here. My personal preference would be staying with log analytics alert generation as much as possible, with use of webhooks.
learn.microsoft.com/en-us/azure/logic-apps/logic-apps-pricing
On another note, usage of any low-code solution such as ADF or logic apps is supposed to make things a bit more pricey (at least in theory), but it might not matter much in the end. The least efficient one would be running the logic app from data factory on scheduled pipelines, even though you are not spending much compute. The most efficient one would be getting an alert generated once a failure is detected, such as using a webhook to send an API call to your slack, without a check that runs every 5 minutes.