You set up a trigger in a spreadsheet by going to the menu Tools -> Script Editor in the spreadsheet. This opens a new script editing window. Copy the code below into the Code.gs tab, replacing the values of the variables in the top 3 lines (dataset_name_or_id, api_key, prod_or_test which can be PROD or TEST depending upon the server you want to update). Then go to the Resources menu and select Current Project's Triggers. Click on the link which says "No triggers set up. Click here to add one now." and set it up as follows using the dropdown menus:
Run: doOnEdit
Events: From Spreadsheet | On edit
Click notifications and from the Execution failure notifications dropdowns, choose the email you want to use and set when to notify as "immediately".
For Google Apps triggers (eg. in Google spreadsheet), please create them with the user hdx.gapps.triggers@gmail.com from Logins.
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