CMPS 340 (File Processing)
Fall 2008
Final Exam Study Guide

• When: Wednesday, December 10, 12:45pm.
• Where: St. Thomas Hall 314? (the usual classroom)
• What to bring: textbook, notes, graded homeworks and programs, hard copy of course web pages.
• Kinds of questions to expect (the majority of which will pertain to material not covered on the first test):
  • File Organization: (fields, records, buckets)
  • Indexing:
    1. Tradeoffs in the concrete vs. abstract pointer/reference issue (i.e., using ``physical'' addresses vs. using logical addresses in the form of a record key (e.g., SSN))
    2. B⁺-trees: insertions and deletions
    3. Extendible Hashing: insertions and deletions
    4. Plain Old Hashing: calculate # of probes required, on average, for searching (both successful and unsuccessful) in a (plain) hash table in which linear probing is used as the collision resolution strategy.
    5. Tradeoffs between tree-based indexing and hash-based indexing
  • External Sorting:
    1. Estimating running time of merging phase of external sorting (see web page)
    2. Replacement Selection technique for producing initial sorted runs larger than available RAM
  • Sequential File Update
  • Database:
    1. Relational Algebra and SQL queries: evaluating and developing
    2. Algorithms for Query Processing (see web page)
    3. Query Optimization
  • Data Coding/Compression/Decompression:
    1. coding, unique decipherability, deciphering delay
    2. Run-length encoding (be prepared to develop an algorithm for compression or decompression)
    3. Huffman compression/decompression
    4. Encoding a Huffman tree as a bit string
    5. Canonical codewords (left-skewed Huffman tree)
    6. LZW compression/decompression
  • Information Retrieval:
    1. Notions of Precision and Recall
    2. Some basic notions regarding measuring the relevance of a document with respect to a query: term frequency (within a document), term scarcity (within the set of documents).
    3. Case Folding, Stemming, and Stop Words