Data Fetcher's no output mode means no records will be created/ updated in your base when an API request runs. This is useful when:
You want to use an API that does not return anything in its response.
You want to ignore any API responses. E.g. because you are making POST requests to send data from Airtable, rather than GET requests to import data.
When you enable no output mode you will not need to set an output table/ view, response field mapping or data transformation. When you enable No output mode these parts of the create request screen will be hidden.