Dear SQLiters, Could some help if this is bad design or my lack of knowledge of SQL:
I have a table that keeps track of bad metrics from exams: badMetric(examID, metric, reason) I want to filter-out bad ones and keep only good ones from the user request: request(examID, metric). I thought: SELECT request.examID, request.metric FROM request, badMetric WHERE NOT (request.examID = badMetric.examID AND request.metric = badMetric.metric) This produces empty list. Is it because the badMetric is actually empty and "FROM request, badMetric" produces cross product of not-empty with empty tables which is an empty table? Is this a bad design and I should add a quality column: badMetric(examID, metric, reason, quality) What could be other solutions? Thank you, Roman _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
