Spent a while on this still cant quite get it. I have some rows in a table like this: 

```
uuid, pos (R|S|N), number (1-10), account (string), xtype (string)

```

A unique row is identified by `uuid, pos,` number

I am trying to write a query that can find occurrences of:

* same uuid where
	+ account = x, pos = R, number = 1
	+ account = x, pos = S, number = 1
	+ no occurrences of pos N
	+ pos R has only a row with number 1, no other occurrences of pos R for this uuid

Hope I have provided enough info, please let me know if you need any more.