Consider the bank database schema as given below:

branch(branch_name, branch_city, assets) customer(customer_name, customer_street, customer_city) loan(loan_number, branch_name, amount) borrower(customer_name, loan_number) account(account_number, branch_name, balance) depositor(customer_name, account_number)

Let us define a view branch_cust as follows:

create view branch cust as select branch_name, customer_name from depositor, account where depositor.account_number = account.account_number

Suppose that the view is materialized; i.e., the view is computed and stored.

a. Write an SQL trigger to maintain the view, i.e., to keep it up to date on insertions to and deletions from depositor or account. Do not bother about updates.

b. Write an SQL trigger to carry out the following action: On delete of an account, for each owner of the account, check if the owner has any remaining accounts, and if he/she does not, delete her from the depositor relation.

Expected Solution: You need to paste the SQL commands for each step.