Suppose you work at a bank as a data analyst. Your main job is to analyze the data stored in their database. The database has five tables, whose schema is shown as below. Primary keys attributes are underlined and foreign keys are noted in the superscript. Customer = {customerID, firstName, lastName, income, birthDate} Account = {accNumber, type, balance, branchNumber FK-Branch} Owns = {customer DFK-Customer, accNumberFK-Account} Transaction = {transNumber, accNumber"K-Account, amount} Employee = {ssn, firstName, lastName, salary, branchNumber FK-Branch Branch = {branch Number, branchName, managerSSNFK-Employce, budget} The answer to each question should be a single SQL query. You must order each query as described in the question, order is always ascending unless specified otherwise Every column in the result should be named. So if the query ask you to return something like income times 10, make sure you include an AS statement to name the column. While your question will not be assessed on their efficiency, marks may be deducted if unnecessary tables are included in the query (e.g., including both Owns and Customer when you only require the customerID of customers who own accounts). You may use some date functions in the following questions. In this homework, you should refer to the date and time functions of MySQL (which is also compatible with MariaDB). For more details, please refer to this page. In this homework, you are NOT allow to use JOIN keyword or subqueries. 17. Return the average income of customers from different age group (where age group is formed in a unit of 10 years, i.e., [0,10), [10,20),...). Note that you can calculate a customer's age by subtracting his/her birth year from the current year. 18. Return customer ID, first name, last name, income and the average account balance of customers who have at least three accounts, and whose last names begin with 's' and contain an 'e' (e.g. Steve) OR whose first names begin with 'a' and have the letter 'n' just before the last 2 letters (e.g. Anne). Note that to appear in the result customers must have at least 3 accounts and satisfy one (or both) of the name conditions. 19. Return account number, balance, sum of transaction amounts, and (balance - transaction sum) for accounts in the London branch that have at least 15 transactions, order by transaction sum. 20. Return customer ID, first name, last name of the customers who have a total account balance in all branches greater than $300,000 but has less than $100,000 in the total balance of their accounts at the New York branch
