3i Infotech Papers: Sample Questions 549 - 551 of 1245

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Question number: 549

» Database » MySQL

Essay Question▾

Describe in Detail

What is Multivalued dependency?

Explanation

Define multivalued dependancy

Define Multivalued Dependancy

Define multivalued dependancy

  • Multivalued dependency occurs when there are more than one independent multivalued attributes in a table.

  • For example:

    • Consider a bike manufacture company, which produces two colors (Black and white) in each model every year.

    Table shows the bike manufacture company

    Table shows the bike manufacture company

    Bike_model

    Manuf_year

    color

    M01

    2008

    Black

    M01

    2008

    Red

    M02

    2011

    Black

    M02

    2011

    Red

    M20

    2015

    Black

    M20

    2015

    Red

  • Columns manuf_year and color are independent of each other and dependent on bike_model. In this case these two columns are said to be multivalued dependent on bike_model.

  • These dependencies can be represented like this:

bike_model - > > manuf_year

Question number: 550

» Languages » C & C Plus Plus

Short Answer Question▾

Write in Short

  1. main ()
  2. {
  3.     clrscr();
  4. }
  5. clrscr();

Explanation

In a program

Table shows the program

Table shows the program

  1. main ()
  2. {
  3.     clrscr();
  4. }

The first clrscr () occurs inside a function.

So, it becomes a function call.

clrscr ();

In the second clrscr (); is a function declaration (because it is not inside any function).

Question number: 551

» Database » Oracle

MCQ▾

Question

What is a trigger

Choices

Choice (4) Response

a.

A piece of logic written in PL/SQL

b.

Executed at the arrival of a SQL * FORMS event

c.

Both a. and b. are correct

d.

Question does not provide sufficient data or is vague

Answer

c.

Explanation

Structure of trigger

Structure of Trigger

Structure of trigger

  • When event occurs a trigger is a like stored procedure that oracle database invokes automatically.

  • Like a stored procedure, we can enable and disable a trigger, but unlike stored procedure we cannot invoke it.

  • It includes a name, and one or more PL/SQL statements- SQL and PL/SQL statements execute as a unit and can invoke stored procedures.

  • Triggered automatically when an associated DML statement is executed.

Benefits of triggers:

  • Generate derived column value automatically.

  • Event storing information on table access

  • Synchronous replication of table.

  • Good security authentication

  • Prevent invalid transaction