How to disable an api call?

Hi all,

I've created a data model which uses a function to call the Microsoft Sentiment Analysis api - everything works really well.

What I want to do is somehow disable the call where records have already been allocated a sentiment score from a previous call. This is because there's a cost per call - once I have a score, I don't need to recall the api.

Below is the function called Sentiment:

let
Sentiment = (inputtext) =>

let
Source = OData.Feed("https://api.datamarket.azure.com/data.ashx/amla/text-analytics/v1/GetSentiment?text="&inputtext),
ToTable = Record.ToTable(Source)

in
ToTable

in
Sentiment

Can anyone advise on the best way to do this?

Best wishes,

Martyn