Abstract: A computerized data retrieval system, especially for commodity price information databases, having a windowing system which aids a user in creating and revising formal search language queries, a database searching engine responsive to such queries, means to generate and format results in both textual and graphic reports, and a capacity for echoing a formal search language query to a display in a near-natural language format for easy comprehension by the user as the query is constructed using the windowing system. The system has facilities for including domain knowledge in a query, such as market knowledge of calendar events, national holidays, triple-witching hours, and option contract expiration dates. The system has additional facilities that permit a user to include more fundamental domain knowledge, such as dates of political elections, date of issuance and value of company earning reports, the consumer price index, and so on.