Quiz Discussion

’_____’ matches any string of ______ three characters. ’_____%’ matches any string of at ______ three characters.

• 1]

  Atleast, Exactly

• 2]

  Exactly, Atleast

• 3]

  Atleast, All

• 4]

  All, Exactly

A ________ in a table represents a relationship among a set of values.

• 1]

  Column

• 2]

  Key

• 3]

  Row

• 4]

  Entry

The _______ operator takes the results of two queries and returns only rows that appear in both result sets.

• 1]

  Union

• 2]

  Intersect

• 3]

  Difference

• 4]

  Projection

SELECT name
FROM instructor
WHERE dept name = ’Physics’
ORDER BY name;

By default, the order by clause lists items in ______ order.

• 1]

  Descending

• 2]

  Any

• 3]

  Same

• 4]

  Ascending

The most commonly used operation in relational algebra for projecting a set of tuple from a relation is

• 1]

  Join

• 2]

  Projection

• 3]

  Select

• 4]

  Union

SELECT name
FROM instructor
WHERE salary <= 100000 AND salary >= 90000;

This query can be replaced by which of the following ?

• 1]

  SELECT name
  FROM instructor
  WHERE salary BETWEEN 90000 AND 100000;

   

• 2]

  SELECT name
  FROM employee
  WHERE salary <= 90000 AND salary>=100000;

   

• 3]

  SELECT name
  FROM employee
  WHERE salary BETWEEN 90000 AND 100000;

   

• 4]

  SELECT name
  FROM instructor
  WHERE salary BETWEEN 100000 AND 90000;

   

SELECT emp_name
FROM department
WHERE dept_name LIKE ’ _____ Computer Science’;

Which one of the following has to be added into the blank to select the dept_name which has Computer Science as its ending string?

• 1]

  %

• 2]

  _

• 3]

  ||

• 4]

  $

The_____ operation allows the combining of two relations by merging pairs of tuples, one from each relation, into a single tuple.

• 1]

  Select

• 2]

  Join

• 3]

  Union

• 4]

  Intersection

SELECT name ____ instructor name, course id
FROM instructor, teaches
WHERE instructor.ID= teaches.ID;

Which keyword must be used here to rename the field name?

• 1]

  From

• 2]

  Rename

• 3]

  As

• 4]

  Join

The _________ provides a set of operations that take one or more relations as input and return a relation as an output.

• 1]

  Schematic representation

• 2]

  Relational algebra

• 3]

  Scheme diagram

• 4]

  Relation flow