Imaginary query language syntax

examples

(collect (filter (intersect student.sid registration.sid) (eq semester "I-2001")) sid sname cid)

(collect (dedup (filter (intersect faculty.fid qualification.fid) (eq (year date_qualified) 1995) fid) fid fname)

(collect (rev (sort (filter (intersect (intersect qualification.fid faculty.fid) course.cid qualification.cid) (eq fname "Ama")) cid)) cname cid)

(collect (dedup (sort (intersect faculty.fid qualification.fid) fname) fid) fid fname)

(collect (filter (intersect registration.cid course.cid) (and (eq semester "I-2001") (eq cname "Syst Analysis")) sid)

(collect (filter (intersect (intersect registration.cid course.cid) student.sid registration.sid) (and (eq semester "I-2001") (eq cname "Syst Analysis")) sid sname)

# giving optional aliases to joined variables (when variables of original tables you are joining are different)
(collect (filter (intersect (intersect course.cid registration.cid cid) registration.sid student.sid sid) (startswith "A")) cname cid sname)

# giving aliases to tables
(collect (dedup (filter (intersect (intersect (alias student s faculty f qualification q registration r) s.sid r.sid) f.fid q.fid) q.cid r.cid) (eq fname "Berry")) sid) sid sname)

(collect (leftjoin faculty.fid qualification.fid) fid fname cid)

(collect (leftjoin (leftjoin faculty.fid qualification.fid) course.cid qualification.cid) fid fname cname)