Needs to understand ordering on different data types.

Need a function tupCompare(r1,r2,f) (cf. C's strcmp)

int tupCompare(r1,r2,f)
{
   if (r1.f < r2.f) return -1;
   if (r1.f > r2.f) return 1;
   return 0;
}

Assume =, <, > are available for all attribute types.