The Database I am creating is a Bank Database. I am using a very simple bank database, which has few tables and will provide very limited capabilities to the bank.
Bank Database:
The bank database I have created has 4 tables: Branch, Account, Depositor and Customer
The details (attributes) of the bank databases are as shown:
i) The branch table contain information about the branch location.
ii) The Account table has information about the balance and the account holder and where he is having a account(which branch).
iii) The Depositor table has information about which Account is associated with which customer.
iv) The customer table has information about the customer like his name, address etc.
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Branch: Branch_name, Branch_city, City_code
Account: Account_number, Branch_name, Balance
Depositor: Customer_name, Account_number
Customer: Customer_name, Customer_street, Customer_city, Phone_number
The underlined attributes are the primary key above.
The SQL statements for creating the above tables are as following:
Branch : Create table branch
(branch_name char(20)
Branch_city char(30)
City_code int
Primary key (branch_name))
Account : Create table account
(account_number char(10)
Branch_name char(20)
balance int
Primary key (account_number))
Depositor : Create table depositor
(customer_name char(20)
account_number char(10))
Customer : Create table customer
(customer_name char(20)
customer_street char(30)
customer_city char(30)
phone_number char(10)
Primary key (customer_name))
This database may provide the following information:
i) The balance present in a customer's Account.
ii) The information about a customer holding a particular Account number X .
iii) How many Customers in the bank has balance less than a some amount Y.
The SQL statements for the above are as follow:
i) To find the balance in account number X
Select balance from from Account where account_number = X
ii) The information about a customer holding a particular Account number X .
Select customer_name, customer_street, customer_city, phone_number from
Customer where customer_name = (select customer name from Depositor
where account_number = X)
iii) How many Customers in the bank has balance less than a some amount Y.
select count(account_number) from Account where balance < Y
Sample Set :
i) Select balance from from Account where account_number = 0111123323
Output :: 2000
ii) Select customer_name, customer_street, customer_city, phone_number from
Customer where customer_name = (select customer name from Depositor
where account_number = 0111123456)
Output :: Customer_name - Hector
Customer_street - bbb
Customer_city - XYZ
Phone_number -- 1982918291
iii) select count(account_number) from Account where balance < 3000
Output :: 2