Intro to database systems: Q7. Formulate the following SQL query in relational algebra using an efficient...
Intro to database systems:
Q7. Formulate the following SQL query in relational algebra using an efficient way. The schema is given in the following. Emp(eno, ename, title, city)
Proj(pno, pname, budget, city)
Works(eno, pno, since)
SELECT ename
FROM Works , Emp
WHERE Works.pno = ‘P150’
AND Works.eno = Emp.eno
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Intro to database systems:
Q7. Formulate the following SQL query in relational algebra
using an efficient...
Consider an Engineering database that maintains three tables: EMP (ENO, NAME, TITLE, SAL) PROJ (PNO, PNAME,...
Consider an Engineering database that maintains three tables: EMP (ENO, NAME, TITLE, SAL) PROJ (PNO, PNAME, BUDGET, LOC) ASG (PNO, ENO, RESP, DUR) EMP stores employee information, including the name, title and salary of the employee. PROJ stores project information, including the name, budget and location of the project. ASG keeps information about the assignment between projects and employees. RESP is the responsibility of the employee, while DUR is the duration that the employee works on the project. ENO is...
can you answer part e of the question Q.31 Answer the following questions (a) Explain difference between lossy decomposition and lossless decomposition (b) If you write a SQL statement to inner jo...
can you answer part e of the question
Q.31 Answer the following questions (a) Explain difference between lossy decomposition and lossless decomposition (b) If you write a SQL statement to inner join the following two tables based on Plocation value as inner join condition, is the result table lossy or lossless? (Explain why?) EMP LOCS P.K EMP PROJ1 Hours Pname Plocation Р.К. (c) Given a relation schema R ={SSN, Ename, Pnumber, Pname, Plocation, Hours) R is decomposed to R1, R2,...
Relational algebra (RA) For the database schema shown below, write RA query for each of the...
Relational algebra (RA) For the database schema shown below, write RA query for each of the following. (State any reasonable assumptions only if necessary) employee (person_name, street, city) works(person_name, company_name, salary) company (company_name, city) Questions: Find person names, streets and cities of employees who work for two different companies. For each company, find person name, salary, street and city for the highest paid employee of that company. For each company, find total number of employees and total number of cities...
HELP DATABASE QU Question 1: Think About the relational database table data as given below, write...
HELP DATABASE QU
Question 1: Think About the relational database table data as given below, write the following queries in Oracle SQL. Company (Cid, Cname, City, Budget, Branch) Department (Deptno, Dname, Building, Cname) Employee (Ename, Deptno, Street, City, Phone, Salary) Works (Ename, Deptno, Hire_date) Location (Cname, Location ) 1. Write Query to Create the Company table, suggest appropriate data type of each attribute, consider that there should be a name for each company. 2. Find employee name/names who live in...
Given the following relational schema, write queries in SQL to answer the English questions. There is...
Given the following relational schema, write queries in SQL to answer the English questions. There is a shipment database on the MySQL server. You can also use the DDL for MySQL. You must only submit the SQL for your answers but you can include the query output as well to help the TA with marking. Customer(cid: integer, cname: string, address: string, city: string, state: string) Product(pid: integer, pname: string, price: currency, inventory: integer) Shipment(sid: integer, cid: integer, shipdate: Date/Time) ShippedProduct(sid:...
Given the following relational schema, write queries in SQL to answer the English questions. There is...
Given the following relational schema, write queries in SQL to answer the English questions. There is a shipment database on the MySQL server. You can also use the DDL for MySQL. You must only submit the SQL for your answers but you can include the query output as well to help the TA with marking. Customer(cid: integer, cname: string, address: string, city: string, state: string) Product(pid: integer, pname: string, price: currency, inventory: integer) Shipment(sid: integer, cid: integer, shipdate: Date/Time) ShippedProduct(sid:...
Answer each of the following questions. The questions are based on the following relational schema: Emp(*eid:...
Answer each of the following questions. The questions are based on the following relational schema: Emp(*eid: integer¬, ename: string, age: integer, salary: decimal, doj: date) Works(*eid: integer, *did: integer, no_of_hours: integer) Dept(*did: integer, dname: string, budget: real, managerid: integer) a) Give an example of a foreign key constraint that involves the Dept relation. b) What are the options for enforcing this constraint when a user attempts to delete a Dept tuple? c) Define the Dept relation in SQL so that...
5.10 Express each of the following queries in relational algebra and (ii) SQL using the Student...
5.10 Express each of the following queries in relational algebra and (ii) SQL using the Student Registration System schema of Figure 3.4. a. List all courses that are taught by professors who belong to the EE or MGT departments. Exercises 189 b. List the names of all students who took courses both in spring 1997 and fall 1998 38 CHAPTER 3 The Relational Data Model FIGURE 3.4 Fragment of the Student Registration database schema STUDENT (Id:INTEGER, Name:STRING, Address:STRING, Statu PROFESSOR...
**************PLEASE COMPLETE PART F) ONLY************** Consider the following relational database schema (primary keys are underlined) and...
**************PLEASE COMPLETE PART F) ONLY************** Consider the following relational database schema (primary keys are underlined) and SQL query: Hotel (hotelNo, hotelName, city) Room (roomNo, hotelNo, type, price) Booking (hotelNo, guestNo, dateFrom, dateTo, roomNo) Guest (guestNo, guestName, guestAddress) SELECT g.guestNo, g.guestName FROM Room r, Booking b, Hotel h, Guest g WHERE h.hotelNo = b.hotelNo AND g.guestNo = b.guestNo AND h.hotelNo = r.hotelNo AND h.hotelName = "Ritz" AND dateFrom >= "Jan 01, 2001" AND dateTo <= "Dec 31, 2001"; (A) state what...
**************PLEASE COMPLETE PART E) ONLY************** Consider the following relational database schema (primary keys are underlined) and...
**************PLEASE COMPLETE PART E) ONLY************** Consider the following relational database schema (primary keys are underlined) and SQL query: Hotel (hotelNo, hotelName, city) Room (roomNo, hotelNo, type, price) Booking (hotelNo, guestNo, dateFrom, dateTo, roomNo) Guest (guestNo, guestName, guestAddress) SELECT g.guestNo, g.guestName FROM Room r, Booking b, Hotel h, Guest g WHERE h.hotelNo = b.hotelNo AND g.guestNo = b.guestNo AND h.hotelNo = r.hotelNo AND h.hotelName = "Ritz" AND dateFrom >= "Jan 01, 2001" AND dateTo <= "Dec 31, 2001"; (A) state what...
can you answer part e of the question
Q.31 Answer the following questions (a) Explain difference between lossy decomposition and lossless decomposition (b) If you write a SQL statement to inner join the following two tables based on Plocation value as inner join condition, is the result table lossy or lossless? (Explain why?) EMP LOCS P.K EMP PROJ1 Hours Pname Plocation Р.К. (c) Given a relation schema R ={SSN, Ename, Pnumber, Pname, Plocation, Hours) R is decomposed to R1, R2,...
HELP DATABASE QU
Question 1: Think About the relational database table data as given below, write the following queries in Oracle SQL. Company (Cid, Cname, City, Budget, Branch) Department (Deptno, Dname, Building, Cname) Employee (Ename, Deptno, Street, City, Phone, Salary) Works (Ename, Deptno, Hire_date) Location (Cname, Location ) 1. Write Query to Create the Company table, suggest appropriate data type of each attribute, consider that there should be a name for each company. 2. Find employee name/names who live in...
5.10 Express each of the following queries in relational algebra and (ii) SQL using the Student Registration System schema of Figure 3.4. a. List all courses that are taught by professors who belong to the EE or MGT departments. Exercises 189 b. List the names of all students who took courses both in spring 1997 and fall 1998 38 CHAPTER 3 The Relational Data Model FIGURE 3.4 Fragment of the Student Registration database schema STUDENT (Id:INTEGER, Name:STRING, Address:STRING, Statu PROFESSOR...
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