Build a SQL table structure with data that will work with theses three queries.

select * from t1 left join t2 using(x);

x | y ---+-------- 1 | (null) 2 | 0 3 | (null) 4 | 0 5 | (null) 6 | 0 7 | (null) 8 | 0 9 | (null) 10 | 0

select t1.* from t1 cross join t1 as t2 cross join t1 as t3 group by t1.x having t1.x=max(t2.x) or t1.x = min(3 * t3.x) order by t1.x;

x

select count(*),sum(x) from t1;

count | sum ------+----- 10 | 55