SQl Query - how can I write this query : 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.  

