6.893 Architecture of Database Systems Term Project

6.893 Architecture of Database Systems
Term Project

Ben Leong
benleong@mit.edu

The Problem - Abstract Data Type Exercise

Implement an abstract data type in POSTGRES that supports "Wall Street Trading Date" (WSTD). This data type is represented externally as a pair (year, integer); for example, (2002, 3) represents the third trading day of 2002 (which I believe is Jan 4th). When, year is not specified, the default is the current year, so 3 represents January 4, 2002. Choose some reasonable internal representation for the WSTD data type and implement the following operations:

Same_year (WSTD-1, WSTD-2) returns Boolean; this returns true if the values are in the same year.
Same_day_of_week (WSTD-1, WSTD-2) returns Boolean; this returns true if the two values are the same day of the week.
Distance (WSTD-1, WSTD-2) returns integer; this returns the number of trading days between the two WSTDs.
Mon (WSTD), Tues (WSTD), Wed (WTD), Thu (WSTD), Fri (WSTD) returns Boolean; these have the obvious interpretation.
DJIA (WSTD) returns float; returns the Dow Jones Industrial Average on this date
Date (WSTD) returns Date; returns the calendar date of the given WSTD.
Greater_than (WSTD-1, WSTD-2) returns Boolean
Less_than (WSTD-1, WSTD-2) returns Boolean
Greater_Equal (WSTD-1, WSTD-2) returns Boolean
Less_Equal (WSTD-1, WSTD-2) returns Boolean
Equals (WSTD-1, WSTD-2) returns Boolean

In addition, POSTGRES should be taught how to construct B-tree indexes on the WSTD type and the optimizer should be taught how to utilize the resulting indexes.

My Solution

I have completed the above project using PostgreSQL 7.1.3 running on a RedHat 7.2 Linux system with kernel version 2.4.9-6. Please click here to see my solution. Have a nice day!