Question

I have a table that is similar to:

cycle | id    | name
------|-------|------
0     | 0012  | bob
s     | 0012  | bob
1     | 0012  | bob
0     | 6208  | sally
1     | 6208  | sally
0     | 3276  | jane
s     | 3276  | jane
1     | 3276  | jane
0     | 8736  | harry
s     | 8736  | harry

I need a query that will result in:

cycle | id    | name
------|-------|------
s     | 0012  | bob
0     | 6208  | sally
s     | 3276  | jane
s     | 8736  | harry

So only return rows that have a ‘cycle’ value of “s”, unless there is no value of “s” for a particular ‘id’ in which case it should return the row with the ‘cycle’ value of “0”.

Answer 1

SELCET cycle, id, name from tbl1 as t1 where cycle='s' or 
(cycle=0 and (select count(cycle) from tbl1 as t2 where t2.id = t1.id and t2.cycle='s') <= 0)
group by t1.cycle,t1.id;