How were the queries chosen?
Member companies of the TPC-D subcommittee were all invited to submit queries for inclusion in TPC-D. Each query submission had to consist of 3 components: 1) A business question, written in English, to prove that the query was asking a sensible business question, 2) Standard SQL syntax that implemented the business question, and 3) A short overview of what SQL functionality was exercised. After the submission period, the proposed queries were analyzed and compared to a survey of decision support customer’s queries. Next, duplicates and queries deemed too simple for a complex query workload were dropped. The remaining queries were rephrased from SQL-89 (using lots of views) to SQL-92 (using nested table expressions and CASE expressions). The result was the 17 Functional Query Definitions presented in Clause 2.