/* ------------------------------------------------------------------------ */
/* Do not edit this part ---------------------------------------------------*/
/* ------------------------------------------------------------------------ */
:- consult('emp.pl').
:- consult('subtotal.pl').
:- consult('query.pl').

%Database emp:
%emp(Empno, Ename, Job, Mgr, Hiredate, Sal, Comm, Deptno)
%dept(Deptno, Dname, Loc)
%salgrade(Grade, Losal, Hisal)

/* ------------------------------------------------------------------------ */
/* Example -----------------------------------------------------------------*/
/* ------------------------------------------------------------------------ */

/* Print all jobs. */
job(J) :-
  emp(_, _, J, _, _, _, _, _).

/* To run this query, use (in another window, after saving this file):
'pl -s queries_emp.pl'
and then (Prolog prompt):
make.
?- q(job(J)). 
*/

/* ------------------------------------------------------------------------ */
/* Write and test the following queries ----------------------------------- */
/* ------------------------------------------------------------------------ */

/* Print names and jobs of employees with salary at least 2000. */

/* Print names and jobs of employees who work in department 30. */

/* Print the number of department in which the president works. */

/* Print names of employees who were hired between 1 September 1981 and 31 October 1981. */

/* Print names and salaries of managers, sort the output in the descending order of salaries. */

/* Print names, brutto incomes, national insurance contributions, income taxes and netto incomes of employees (subtract 13.4% for national insurance and 19% for income tax). */

/* Print names and the number of working years (since hired) of all employees. */

/* Print names of all employees with the first letters of their department names. */

/* Print name and "total salary" (total salary = salary + comm) of each employee. (Warning: the column comm may contain NULL values.) */

/* Print jobs of employees who work in Chicago. */

/* Print tuples [Name, City, Coworker] which stand for all employees, their working places and names of their co-workers (employees who work in the same department). */

/* Print names, department names and salaries of all employees whose salaries are greater than the lowest salary in department 20. */

/* Print names of employees together with names of their managers. */

/* Which departments contain all job positions? */

/* Which departments are empty (have no employees)? */

/* Which employees manage only clerks? */

/* Which departments employ no salesmen? */

/* Find names of all employees who are subsidiaries of Blake - both direct and indirect subsidiaries. (This query is a tricky one, skip it unless you understand what precisely you are doing.) */