Lunch together calc

gistfile1.txt

#Detail
SELECT username,(cost) FROM posts, users 
WHERE 
	consumer_id = 2 && 
	posts.payer_id = users.id &&
	payer_id <> 2

#Summary
SELECT username,SUM(cost) FROM posts, users 
WHERE 
	consumer_id = 2 && 
	posts.payer_id = users.id &&
	payer_id <> 2
GROUP BY 
	username
-----------
#Detail
SELECT username, (cost) FROM posts, users 
WHERE 
	consumer_id <> 2 && 
	posts.consumer_id = users.id &&
	payer_id = 2

#Summary
SELECT username, SUM(cost) FROM posts, users 
WHERE 
	consumer_id <> 2 && 
	posts.consumer_id = users.id &&
	payer_id = 2
GROUP BY 
	username