To update a row or rows in a table, use the PATCH verb. Use Horizontal Filtering to specify which record(s) to update. Here is an example query activating a webhook. 
curl "https://api.getmateo.com/api/v1/webhook?id=1234" \
 -X PATCH -H "Content-Type: application/json" \
 -d '{ "active": true }'

HTTP/1.1 204 No Content
No response body will be returned by default but you can add a select query parameter to select the columns that should be returned: 
curl "https://api.getmateo.com/api/v1/webhook?id=1234&select=id,name,active" \
 -X PATCH -H "Content-Type: application/json" \
 -d '{ "active": true }'

HTTP/1.1 200 OK

{
  "id": 1234,
  "name": "My Webhook",
  "active": true
}