Write the Relation Model, using SQL, for the gig Relationship Set shown in this ER Model: The Band and Venue Entity Sets both have the conflicting name as their Primary Keys. Only the gig relation needs to be defined for this question.

Use a suitable example to provide a thorough description of the relational model.

Although SQL does not support functional dependency constraints, if thedatabase system supports constraints on materialized views, and materialized views are maintained immediately, it is possible to enforce functional dependency constraints in SQL. Given a relation r(A, B, C), explain how constraints on materialized views can be used to enforce the functional dependency B → C.

Consider the relations Courses1, Courses2, _Enrollment and Students. Courses1 Location cid cname Al Calculus LI A2 Algebra L2 A5 English L3 Student(sid, sname, age, level) Courses2 cid A5 BI B2 name English History b) Courses 1-Courses2 L3 L4 Computing L5 c) Courses Courses2 Classroom d) Courses1 Enrollment (1) Give the results of the following relational algebra expressions: a) Teid ( name='History' OR 'Computing (Courses2)) e) Enrollment / Teid (Courses1) Enrollment cid Al A5 sid 101 102 103 102 102 B1 Al A2 (2) Write the following query in Relational Algebra. a) Find the sids of students who have enrolled in _course Calculus. b) Find the names of students who have enrolled in course Calculus. _c) Find the names of students who have enrolled at least one course. d) Find the names of students who have enrolled in _Calculus or Algebra. e) Find the sids of students who have enrolled in all courses (both Courses1 and Courses2).

For the attached database, use relational algebra and find the loan_numbers only for the loans with the smallest loan amounts. (Using renaming and set difference). Which database relation(s) could be joined with the result of the query of the previous inquiry to find the Id, name, city, and loan amount for the borrowers having the smallest loan amount?

The reader to formulate some sample queries as relational algebra ex-pressions. (By way of an interesting variation on these "query" exercises, the reader might like to try looking at some of the answers first and stating what the given expression means in English.) 1. Get full details of all projects in London. 2. Get supplier numbers for suppliers who supply project J I. 3. Get all shipments where the quantity is in the range 300 to 750 inclusive. 4. Get all pan-color/part-city combinations. Note Here and in subsequent exercises, the term "all" is to be taken to mean "all currently represented in the database," not "all possible."  

How do you represent an associative entity in a relational data model?

The set of output data in a relationship is called the direct variation range domain function notation

Please draw an relational ERD with multiplicities and all the attributes based on following description: ( Please identify the primary key in each entity.)   An Adult Education Department runs various courses during the daytime and evenings, and at different times of the year. For example, ‘Spanish level 1’ is offered on Monday mornings, Monday evenings or Wednesday evenings, and runs over 25 weeks from October to March. On the other hand, ‘Introduction to Digging Up Your Ancestors’ only runs for 8 weeks, but is offered on Tuesday or Wednesday evenings from October to December, January to March, and April to June, with an optional field week in August.               There is always a maximum number of places for each course offering, which is dependent on the individual teacher. For example, ‘Spanish level 1’ on Monday evenings may be limited to 20 places, but on Wednesday evenings the limit may be 25. Each course offering is only taken by one teacher, however teacher may take…

Computer Science Design an Extended Entity Relationship Model with appropriate cardinality and appropriate entity names which can later be used in SQL to test queries and validate entity relations for the following case. The car hire company caters for both corporate and individual customer hire. Corporate customers are allocated a type, gold, silver or bronze based on the frequency of hire arranged in the contract. Vehicles on corporate and/or individual hire can be collected at any centre and dropped at any centre (with no surcharge for a different centre). Hire charges are based on vehicle classifications (e.g. Luxury Saloon, Basic Hatchback ....) Each classification will include a variety of models (e.g. Ford Fiesta 1.1, Fiat Panda ....are in the ‘Basic Hatchback’ classification). Charges for classifications are by the day. A customer collecting a car at a particular centre will be charged according to the charges for that centre.