delete from works_on;
delete from project;
delete from employee;
delete from department;

insert into employee values(25348, 'Matthew', 'Smith',    'd3');
insert into employee values(10102, 'Ann',     'Jones',    'd3');
insert into employee values(18316, 'John',    'Barrimore','d1');
insert into employee values(29346, 'James',   'James',    'd2');
insert into employee values(9031,  'Elke',    'Hansel',   'd2');
insert into employee values(2581,  'Elsa',    'Bertoni',  'd2');
insert into employee values(28559, 'Sybill',  'Moser',    'd1');

insert into department values ('d1', 'Research',   'Dallas');
insert into department values ('d2', 'Accounting', 'Seattle');
insert into department values ('d3', 'Marketing',  'Dallas');

insert into project values ('p1', 'Apollo', 120000.00);
insert into project values ('p2', 'Gemini', 95000.00);
insert into project values ('p3', 'Mercury', 186500.00);

insert into works_on values (10102, 'p1',  'Analyst',   '2006.10.1');
insert into works_on values (10102, 'p3',  'Manager',   '2008.1.1');
insert into works_on values (25348, 'p2',  'Clerk',     '2007.2.15');
insert into works_on values (18316, 'p2',  NULL,        '2007.6.1');
insert into works_on values (29346, 'p2',  NULL,        '2006.12.15');
insert into works_on values (2581,  'p3',  'Analyst',   '2007.10.15');
insert into works_on values (9031,  'p1',  'Manager',   '2007.4.15');
insert into works_on values (28559, 'p1',  NULL,        '2007.8.1');
insert into works_on values (28559, 'p2',  'Clerk',     '2008.2.1');
insert into works_on values (9031,  'p3',  'Clerk',     '2006.11.15');  
insert into works_on values (29346, 'p1',  'Clerk',     '2007.1.4');