I ran your SQL on 32-bit and 64-bit Linux hosts (virtual and physical, respectively) running
Oracle 11.1.0.7 with ArcSDE 9.3.1sp2 (32-bit) and ArcSDE 10.0sp0 (64-bit) and saw
execution times of 7.5 and 1.6 seconds.
Whatever the cause for the difference, it certainly doesn't look like anything that Esri can
control.
- V