Re: Things that are hard to do in SQL (datamining?)

Erratum: >Date: Sun, 30 Oct 1994 12:10:43 +0800 >From: johnl@informix.com (Jonathan Leffler) >Subject: Re: Things that are hard to do in SQL (datamining?) >X-Informix-List-Id: <list.4956> > ... >We need a list of courses attended by people in departments, with a count >of the number of times the course has been attended: >-- Query 1 > SELECT UNIQUE A.Dept, A.Course_id > FROM Employee E, Attended A > WHERE E.Dept = A.Dept > INTO TEMP Dept_Courses; > ... This SELECT statement was revised after progressing most of the way through the answer, and the COUNT(*) and GROUP BY clauses which made the "with a count of ..." clause valid were removed. The statement should read: We need a list of the courses and departments such that each course listed has been attended by somebody from the named department. Sorry, Jonathan Leffler (johnl@informix.com) #include <disclaimer.h>