Quiz Discussion

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 * FROM employee WHERE dept_name="Comp Sci";

In the SQL given above there is an error . Identify the error.

• 1]

  Dept_name

• 2]

  Employee

• 3]

  “Comp Sci”

• 4]

  From

SELECT instructor.*
FROM instructor, teaches
WHERE instructor.ID= teaches.ID;

This query does which of the following operation?

• 1]

  All attributes of instructor and teaches are selected

• 2]

  All attributes of instructor are selected on the given condition

• 3]

  All attributes of teaches are selected on given condition

• 4]

  Only the some attributes from instructed and teaches are selected

Course(course_id,sec_id,semester)

Here the course_id,sec_id and semester are __________ and course is a _________

• 1]

  Relations, Attribute

• 2]

  Attributes, Relation

• 3]

  Tuple, Relation

• 4]

  Tuple, Attributes

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

A ________ is a pictorial depiction of the schema of a database that shows the relations in the database, their attributes, and primary keys and foreign keys.

• 1]

  Schema diagram

• 2]

  Relational algebra

• 3]

  Database diagram

• 4]

  Schema flow

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

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

Student(ID, name, dept name, tot_cred)
In this query which attributes form the primary key?

• 1]

  Name

• 2]

  Dept

• 3]

  Tot_cred

• 4]

  ID