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Joe Celko s SQL for Smarties - Advanced SQL Programming P22. In the SQL database community, Joe Celko is a well-known columnist and purveyor of valuable insights. In Joe Celko's SQL for Smarties: Advanced SQL Programming, he picks up where basic SQL training and experience leaves many database professionals and offers tips, techniques, and explanations that help readers extend their capabilities to top-tier SQL programming. Although Celko denies that the book is about database theory, he nevertheless alludes to theory often to buttress his practical points. This title is not for novices, as the author points out. Instead, its intended audience. | 182 CHAPTER 5 CHARACTER DATA TYPES IN SQL d. SCH SSS PH FF e. H If previous or next character is a consonant use the previous character. f. W If previous character is a vowel use the previous character. Add the current character to result if the current character is to equal to the last key character. 5 If last character is S remove it 6 If last characters are AY replace them with Y 7 If last character is A remove it The stated reliability of NYSIIS is 98.72 with a selectivity factor of .164 for a name inquiry. This was taken from Robert L. Taft Name Search Techniques New York State Identification and Intelligence System. 5.4 Cutter Tables Another encoding scheme for names has been used for libraries for more than 100 years. The catalog number of a book often needs to reduce an author s name to a simple fixed-length code. While the results of a Cutter table look much like those of a Soundex their goal is different. They attempt to preserve the original alphabetical order of the names in the encodings. But the librarian cannot just attach the author s name to the classification code. Names are not the same length nor are they unique within their first letters. For example Smith John A. and Smith John B. are not unique until the last letter. What librarians have done about this problem is to use Cutter tables. These tables map authors full names into letter-and-digit codes. There are several versions of the Cutter tables. The older tables tended to use a mix of letters both upper- and lowercase followed by digits. The three-figure version uses a single letter followed by three digits. For example using that table Adams J becomes A214 Adams M becomes A215 Arnold becomes A752 Dana becomes D168 Sherman becomes S553 Scanlon becomes S283 5.4 Cutter Tables 183 The distribution of these numbers is based on the actual distribution of names of authors in English-speaking countries. You simply scan down the table until you find the place where your name would fall and use that
