Views adds "nid" to SELECT and GROUP BY when trying to aggregate by title I tried to create a simple aggregated View, but Views added nid, even though I did not select it as a field, and also ruined my GROUP BY making the view unusable.

Any tips how to avoid this nid addition?

SELECT node.title AS node_title_1, node.nid AS nid, COUNT(node.title) AS node_title
FROM 
{node} node
WHERE (( (node.type IN  ('my type')) ))
GROUP BY node_title_1, nid
LIMIT 10 OFFSET 0
Try to enable checkbox Query settings -> Distinct in your view settings.