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

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

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 * 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

The _______operation performs a set union of two “similarly structured” tables

• 1]

  Union

• 2]

  Join

• 3]

  Product

• 4]

  Intersect

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

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;

   

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

For each attribute of a relation, there is a set of permitted values, called the ________ of that attribute.

• 1]

  Domain

• 2]

  Relation

• 3]

  Set

• 4]

  Schema