Preface:
--------
This ket of six tables represents the relations regarding 
an insurance database. A customer can debit (reumbersment) the account, 
credit it (payment) and claim (demand for due). A customer also 
is registered in  a certain branch with a certain policy number.
The schema of an insurance is more developed. Here is just a simple 
example.

1. Creating the tables:
-----------------------

create table customer
(customer_name 	varchar(20)	not null,
customer_street 	varchar(12)	not null,
customer_city 	varchar(15)	not null,
primary key(customer_name));


create table branch
(branch_name 	varchar(15)	not null,
branch_city 	varchar(15)	not null,
balance 		number		not null,
primary key(branch_name));


create table policy
(policy_number 	varchar(20)	not null,
branch_name		varchar(15)	not null,
premium 		number		not null,
primary key(policy_number));


create table claim
(claim_number 	varchar(15)	not null,
branch_name		varchar(15)	not null,
amount 		number		not null,
primary key(claim_number));

create table credit
(customer_name 	varchar(20)	not null,
policy_number 	varchar(20)	not null,
primary key(customer_name, policy_number),
foreign key(policy_number) references policy(policy_number),
foreign key(customer_name) references customer(customer_name));

create table debit
(customer_name 	varchar(20)	not null,
claim_number 	varchar(15)	not null,
primary key(customer_name, claim_number),
foreign key(customer_name) references customer(customer_name),
foreign key(claim_number) references claim(claim_number));

2. Populating the tables:
-------------------------

insert into customer	values ('Planck','Pyramids','Atlanta');
insert into customer	values ('Sommerfeld','Des Jardins',	'3 Rivieres');
insert into customer	values ('Dirac','Potsdam','New Jersey');
insert into customer	values ('De Broglie','Sainte Anne','Toronto');
insert into customer	values ('Heisenberg','Mac Donalds','Montreal');
insert into customer	values ('Rutherford','Concordia','Paris');
insert into customer	values ('Pauli','Des Moines','Sevilla');
insert into customer	values ('Born',	'Opera','plattsburgh');
insert into customer	values ('Boltzmann','Sherbrooke','Ottawa');


insert into branch	values ('1A5',	'Toronto',3456);
insert into branch	values ('2A6',	'Atlanta',3456);
insert into branch	values ('3A4',	'Montreal',	2347);
insert into branch	values ('4D3',	'New Jersey',8765);
insert into branch	values ('2B4',	'Montreal',8790);
insert into branch	values ('5G5',	'Toronto',3000);
insert into branch	values ('7H6',	'Sevilla',4569);
insert into branch	values ('7N9',	'Ottawa',3456);


insert into policy	values ('11EE',	'3A4',2233);
insert into policy	values ('23DD',	'4D3',4563);
insert into policy	values ('34RR',	'3A4',2255);
insert into policy	values ('66TT',	'7H6',439);
insert into policy	values ('56NN',	'7N9',346);
insert into policy	values ('34BB',	'5G5',567);
insert into policy	values ('49SS',	'5G5',2230);
insert into policy	values ('90LL',	'2B4',556);

insert into claim	values ('C2345','2B4',324);
insert into claim	values ('C4568','4D3',5643);
insert into claim	values ('C8765','2B4',456);
insert into claim	values ('C6789','5G5',76);
insert into claim	values ('C4589','3A4',345);
insert into claim	values ('C4567','7H6',234);
insert into claim	values ('C1122','2A6',7890);
insert into claim	values ('C5611','7N9',234);
insert into claim	values ('C0044','7N9',234);


insert into credit values ('Dirac','34RR');
insert into credit values ('Heisenberg','66TT');
insert into credit values ('Planck','34BB');
insert into credit values ('Sommerfeld','49SS');
insert into credit values ('Born','23DD');
insert into credit values ('Planck','56NN');
insert into credit values ('Dirac','11EE');


insert into debit values ('Planck',	'C6789');
insert into debit values ('Dirac','C2345');
insert into debit values ('Sommerfeld',	'C1122');
insert into debit values ('Dirac','C4589');
insert into debit values ('Pauli','C8765');
insert into debit values ('Dirac','C5611');
insert into debit values ('Rutherford','C4567');
insert into debit values ('Pauli','C0044');

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