Indexing & Hashing

1. Many queries reference only a small proportion of records in a file. For example, finding all records at Perryridge branch only returns records where bname = ``Perryridge''.
2. We should be able to locate these records directly, rather than having to read every record and check its branch-name. We then need extra file structuring.

• Basic Concepts
• Ordered Indices
  • Primary Index
    • Dense and Sparse Indices
    • Multi-Level Indices
    • Index Update
  • Secondary Indices
• B -Tree Index Files
  • Structure of a B -Tree
  • Queries on B -Trees
  • Updates on B -Trees
  • B -Tree File Organization
• B-Tree Index Files
• Static Hashing
  • Hash File Organization
    • Hash Functions
    • Handling of bucket overflows
  • Hash Indices
• Dynamic Hashing
• Comparison of Indexing and Hashing
• Index Definition in SQL
• Multiple-Key Access
  • Grid File
  • Partitioned Hashing