> On Feb 16, 2015, at 4:22 AM, josef.gschwendt...@quattro-soft.de > [firebird-support] <firebird-support@yahoogroups.com> wrote: > > we have 2 tables > For each record in Table1 there are 2 records in Table2. > > Table1 (T1) > == > 1 > 2 > > > Table2 (T2) > > T2 T1 > ====== > 1 1 > 2 1 > 3 2 > 4 2 > > What is the cheapest way to get a dataset like below? > > T1 T2a T2b > =========== > 1 1 2 > 2 3 4 >
Can't guarantee it's the cheapest, but you might try select T1.T1, max T2.T1 T2a, max T2.T2 T2B from T1 inner join T2 on T1.T1 = T2.T1 group by T1.T1 Good luck, Ann