Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Consider the subsequent relations for a database which keeps track of business trips of salespersons in a sales office: SALESPERSON (SSN, Name, start_year, Dept_no) TRIP (SSN, From_city, To_city, Departure_Date, Return_Date, Trip_ID) EXPENSE(TripID, Account#, Amount) Specify the subsequent queries in relational algebra: (i) Give the details (all attributes of TRIP) for trips which exceeded $2000 in expenses.(ii) Print the SSN of salesman who took trips to ‘Honolulu'(iii) Print the trip expenses incurred through the salesman with SSN= ‘234-56-7890'.Note in which the salesman might have gone on more than one trip. List them individually
Ans: (i) πTRIP.* (σ amount > 2000 (TRIP EXPENSE)) (ii) π SSN (σ to_city = ‘Honolulu' (TRIP))(iii) πEXPENSE.tripid, amount (σ SSN = ‘234-56-7890' (TRIP EXPENSE))
Consider student (std_id, std_name, date_of_birth, phone, dept_name). Put the data for a student with student id200, name arun, birth date 1 February, 1985, phone number (01110 328
what is multivalued dependency
What subschema expresses ? A subschema expresses the external view. (External schemas are called also called as subschemas)
Synonyms It allows short names or alternative names for objects. Example : CREATE SYNONYM D30 FOR EMPD30; Now if we give command:
Define the terms 1) physical schema 2) logical schema. Physical schema: The physical schema explains the database design at the physical level, which is the lowest lev
3. (10 points) Assume that you have been presented with the following relation for the Baxter Aviation database: Charters (Pilot#, Pilot name, Aircraft ID#, #seats, Village, Fligh
External failure : A failure can also result because of an external cause, such as earthquakes, fire, floods, etc. The database must be duly backed up to avoid troubles occurring d
In a Hierarchical model of data records are organized ? In the hierarchical model of data records are organized as Tree structure.
The Maximum no of key fields that can be used in a header is?? 50
Describe sequential file organization. Explain the rules for (i) Inserting a new record. (ii) Deleting an existing record. Ans:A sequential f
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd