Computers and Technology, 01.03.2021 21:30, godzilla24
Based on the relational schema below:
Emp(eid: integer, ename: string, age: integer, salary: real)
Works(eid: integer, did: integer, pcttime: integer)
Dept(did: integer, dname: string, budget: real, managerid: integer)
Express the following queries in Relational Algebra. Please make use of the aggregate relational algebra operators that was explained in class. If you believe you cannot express a given query in relational algebra, explain why not. Or if you end up making some additional assumptions in order to express the queries using relational algebra, please state your assumption clearly.
Required:
a. Find the names and ages of each employee who works in both the Hardware department and the Software department (assume that Hardware Dept ID =0 and Software Dept ID = 1).
b. Find the mamagerids of managers who manage only departments with budgets greater than $1,000,000. Please note that if a manager manages dept 1 and dept 2 and dept 1 has a budget of 2,000,000 and dept 2 has a budget of 10,000, then the manager would not be included in the result list.
c. For each department with more than 20 full-time-equivalent employees (i. e., where the part-time and full-time employees add up to at least that many full-time employees), find the did together with the number of employees which work in that department.
d. Find the name and age of the oldest employee in each department.
e. Find the department with the highest average age of employees.
Answers: 2
Other questions on the subject: Computers and Technology
Computers and Technology, 21.06.2019 19:30, davisparker5269
Write a function processpeople() that takes the name of a file as a parameter. each line of the file corresponds to information about a person. in particular a line contains either a name (in the form lastname, firstname with no spaces in it) or a name (lastname, firstname) and a year. the function will process the file, creating a person object for each line in the file. the function will print information about each line as it processes it, as well as appending the new person object into a list. make sure to use person methods to display information rather than recreating the work you did for the first problem. once the entire file has been processed, the function returns the list of person objects created from the file. if the file is empty, the function should return an empty list. if the input file cannot be opened, the function should print a message to that effect and then return an empty list. the following shows what would be displayed for two example files which have been provided in the link. the file none. txt does not exist. note that your function must work on an arbitrary file that consists of valid lines. you cannot assume anything about the file except that it contains lines that have the format described above.
Answers: 2
Computers and Technology, 23.06.2019 06:30, jayjay5246
Which option correctly describes a dbms application? a. software used to manage databases b. software used to organize files and folders c. software used to develop specialized images d. software used to create effective presentations
Answers: 1
Do you know the correct answer?
Based on the relational schema below:
Emp(eid: integer, ename: string, age: integer, salary: real)<...
Questions in other subjects:
Mathematics, 24.08.2019 19:50
SAT, 24.08.2019 19:50
English, 24.08.2019 19:50
Social Studies, 24.08.2019 19:50
Business, 24.08.2019 19:50
English, 24.08.2019 19:50
