Material : Relational Algebra Course : Database Systems Create a Relational Algebra From Entity Relational Diagram (ERD) Below for: a) Displays books published in the last 5 years from 2020. b) Displays details of customers who have done shopping (using the Join operator) c) Displays email customers who have done shopping (using the Set operator) d) Displays the ISBN book that has never been purchased (using the Set operator)

Access Assignment   Problem: JMS TechWizards is a local company that provides technical services to several small businesses in the area. The company currently keeps its technicians and clients’ records on papers. The manager requests you to create a database to store the technician and clients’ information. The following table contains the clients’ information. Client Number Client Name Street City State Postal Code Telephone Number Billed Paid Technician Number AM53 Ashton-Mills 216 Rivard Anderson TX 78077 512-555-4070 $315.50 $255.00 22 AR76 The Artshop 722 Fisher Liberty Corner TX 78080 254-555-0200 $535.00 $565.00 23 BE29 Bert's Supply 5752 Maumee Liberty Corner TX 78080 254-555-2024 $229.50 $0.00 23 DE76 D & E Grocery 464 Linnell Anderson TX 78077 512-555-6050 $485.70…

SQL Question~ Write SQL expression to list flight_no and airline_code of all the bookings for customers with first name Sam and city Chicago

Alternate keys: Identify at least five keys (not already listed as PK or FK) needed by end users. These indexes would be considered Alternate or Secondary keys and are mostly used for queries and quick reporting. They may contain multiple columns.

Database Systems please help me answer this question I will give you a good rating Thank you!

Please refer to the following diagram for Q19 to Q20. PERSON PK P_ID P_LNAME P_FNAME ΕMPLOYΕ P_ID EMP_HIRE_DATE STUDENT P ID STUDY ΜAIOR PK, FK1 PK, FK1 19. Which of the following statements is/are true? (1) A Person must be either a Student or an Employee. (2) A Person can neither be a Student nor an Employee. (3) A Person must be a Student or an Employee or both. a. (1) only b. (3) only c. (1) and (2) only d. (1), (2) and (3).

SQL Query Relational Algebra select avg(customer.age) as "avg_age" from AVG(avg_age) (customer) customer; 1. Select customer phone, customer.address, customer.fullname from customer where exists (select * from billing where billing.cid = customer. Customer id); 2. Select * from customer where customer.address in ('Ibri'); 3. Select billing.bill id from billing Group by bill id Having count (case when billing.b status = 'REJWCTED' then 1 end) >1; select * from customer order by full name, age;

Describe problems you might encounter when using the NATURAL JOIN keywords to perform join operations

Assume the EMPLOYEE table contains four attributes, ID, DEPT, SALARY and NAME, and has the following rows ID      DEPT     SALARY   NAME    100   SALES     40000       Smith     101     RD         38000       Terry     102     HR         60000       David     103   SALES    58000       Ellie     104      RD       70000       Judy The DEPARTMENT table contains two attributes, DEPTNAME and PHONE, and has the following rows:  DEPTNAME    PHONE     RD               8596001234     SALES        8596005555    HR              8596009876  A.) The EMPLOYEE table needs to enforce the following integrity constraints: • The ID is the primary key.  • The DEPT column is a foreign key that references the DEPTNAME in the DEPARTMENT table, so that any value that appears in the DEPT column should also exist in the DEPARTMENT table.  • The value for the NAME column can never be null.  What should be the statement used to create the EMPLOYEE table, if 1) the table was created as a partitioned table such…