Use of indexes

Use of indexes

• Treat indexes as a smaller file, scan
  • Benefit O(c)
• Sort each index, do binary (memory) or block search
  • Benefit O(log2N) if indices (index entries) unique
  • not true for images, many features, few significant values
  • Benefit O(Flog2N)
  • and select indexes in order of effectiveness
• Create new combined indexes: Benefits vary
  • Trees: alternating layers in the block hierarchy
  • Weighted sums, . . . more later

Previous slide

Next slide

Back to the first slide

View Graphic Version