Quiz Discussion

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

The ______ clause allows us to select only those rows in the result relation of the ____ clause that satisfy a specified predicate.

• 1]

  Where, from

• 2]

  From, select

• 3]

  Select, from

• 4]

  From, where

Database __________ which is the logical design of the database, and the database _______ which is a snapshot of the data in the database at a given instant in time.

• 1]

  Instance, Schema

• 2]

  Relation, Schema

• 3]

  Relation, Domain

• 4]

  Schema, Instance

The tuples of the relations can be of ________ order.

• 1]

  Any

• 2]

  Same

• 3]

  Sorted

• 4]

  Constant

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

In SQL the spaces at the end of the string are removed by _______ function.

• 1]

  Upper

• 2]

  String

• 3]

  Trim

• 4]

  Lower

Using which language can a user request information from a database?

• 1]

  Query

• 2]

  Relational

• 3]

  Structural

• 4]

  Compiler

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;

   

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