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Exercise 4: Query Types

Using the relation: 

create table Courses (
   id       integer primary key,
   code     char(8),  -- e.g. 'COMP9315'
   title    text,     -- e.g. 'Computing 1'
   year     integer,  -- e.g. 2000..2016
   convenor integer references Staff(id),
   constraint once_per_year unique (code,year)
);

give examples of each of the following query types:

  1. a 1-d one query,    an n-d one query
  2. a 1-d pmr query,    an n-d pmr query
  3. a 1-d range query,    an n-d range query

Suggest how many solutions each might produce ...