Databse Management questions

Mark T(rue) or F(alse) for each statement below. Heap file is very efficient for insert operations ( ). X ( ZWV can be decomposed into X (ZW and X (V. ( ) The following SQL query is syntactically correct. ( ) SELECT x, y, z, count(*) FROM t1, t2 WHERE x = w GROUP BY x, y ; If 2NF relation R does not have composite keys, then R is in 3NF. ( ) Functional dependencies in a given relation cannot be changed after updates of tuples. ( ) The field for a clustering index is a non-key field. ( ). Briefly Explain (5 points) List all nontrivial functional dependencies satisfied by the relation of the Figure below: A B C a1 b1 c1 a1 b1 c2 a2 b1 c1 a2 b1 c3 (3 points) Person(SSN: String, Name: String, PhoneN: {String}, Child: {Person}) Object-based query: SELECT P.Child.Child.PhoneN FROM Person P WHERE P.Name = ‘Joe Public’ What does this query do? Suppose we have a table EMP (SSN, First_name, Last_name, DOB, Phone). Write a SQL statement that displays the concatenated full name and age of all the employees whose phone numbers begin with area code begins with 215. Display the full name as full_name. Is it possible in general to have two primary indices on the same relation for different search keys? Explain your answer briefly. Answer: I would say no. It is not possible to have two primary indices of or on the same relation for different key. This can only be done if the relation is stored in a different order in order t have the duplicate values stored together. Which of the following index types is best suited for a column with a high cardinality (choose only one of the following options)? Composite B*-Tree Bitmap Other Which of the following is not a benefit of indexes (choose only one of the following options)? Faster operation during INSERT commands Faster...