Deck 9: Database Triggers

Question 1

LOB and OBJECT columns can be referenced in a trigger and can also be modified.

Answer 1

False

Question 2

System triggers are typically used to allow the modification of data through a view on a view that is nonmodifiable.

Answer 2

False

Question 3

LONG RAW variables cannot be declared in triggers. _________________________

Answer 3

True

Question 4

The timing of triggers must be indicated as either BEGIN or END.

Question 5

If multiple triggers exist on a table, there is no guarantee about the order in which the triggers will be fired.

Question 6

A(n) mutating table is one that is referenced via a foreign key constraint on the table that a trigger is modifying. _________________________

Question 7

The WHEN clause of a trigger can be used only in row level triggers. _________________________

Question 8

LONG or LONG RAW variables can be declared in triggers and the NEW and OLD qualifiers cannot refer to these types of columns.

Question 9

Using the MULITPLE TRIGGER clause will allow more than one triggering event to be included in a single trigger.

Question 10

Numerous triggers can be constructed on one table and, therefore, a DML action on that table can fire off more than one trigger.

Question 11

A database trigger is tied to a database table or view and is implicitly fired by the database system when that table or view is affected with the associated DML action.

Question 12

Only one triggering event can be addressed in a single trigger.

Question 13

A constraining table is one that is being modified by a DML action when a trigger is fired.

Question 14

The trigger body is a PL/SQL block that contains the actions that take place when the trigger fires.

Question 15

One prominent limitation in the use of triggers is that they cannot issue transaction control statements of COMMIT, ROLLBACK, and SAVEPOINT.

Question 16

To remove a trigger from the system, the DEL TRIGGER statement is used. _________________________

Question 17

The FOLLOWS trigger option enables a developer to control the firing order of triggers.

Question 18

Correlation identifiers allow us to refer to and use the row data values of a DML action. _________________________

Question 19

The ALTER TRIGGER statement is used to recompile, enable, or disable a trigger.

Question 20

The default timing of a trigger is row level and no code is included to achieve this timing.

Question 21

CREATE [OR REPLACE] TRIGGER trigger_name [BEFORE, AFTER]
[List of DDL or Database System Events] [ON DATABASE |
SCHEMA] Trigger body;
The syntax above represents that of a(n) ____ trigger.

A) statement
B) row level
C) system
D) Instead-Of

Question 22

The statement ____ can be used to disable or enable a specific trigger.

A) ANALYZE TRIGGER trigger_name DISABLE|ENABLE;
B) ALTER TRIGGER trigger_name DISABLE|ENABLE;
C) AUDIT TRIGGER trigger_name DISABLE|ENABLE;
D) GRANT TRIGGER trigger_name DISABLE|ENABLE;

Question 23

A(n) ____ is a table that is being modified by a DML action when a trigger is fired.

A) system table
B) mutating table
C) transaction table
D) correlation table

Question 24

Which of the following events will cause the trigger to fire?
AFTER UPDATE OF orderplaced ON bb_basket

A) INSERT
B) UPDATE
C) DELETE
D) AFTER

Question 25

The default timing of a trigger is ____.

A) statement level
B) system level
C) row level
D) header level

Question 26

DDL events include all of the following, except ____.

A) ALTER
B) DROP
C) GRANT
D) DECLARE

Question 27

Row level options are only applicable for ____ events.

A) CREATE
B) INSERT
C) DECLARE
D) UPDATE and DELETE

Question 28

Which of the following statements is True about mutating tables?

A) A table in an UPDATE statement that fires a row level trigger affecting the same table is not considered a mutating table unless the UPDATE includes a subquery.
B) A table in a DELETE statement that fires a row level trigger affecting the same table is not considered a mutating table unless the DELETE includes a subquery.
C) A table in an INSERT statement that fires a row level trigger affecting the same table is not considered a mutating table unless the INSERT includes a subquery.
D) A table in a DROP statement that fires a row level trigger affecting the same table is not considered a mutating table unless the DROP includes a subquery.

Question 29

All of the following would cause a trigger to fire, except ____.

A) BEFORE
B) INSERT
C) DELETE
D) UPDATE

Question 30

CURSOR basketitem_curIS
SELECT idproduct, quantity, option1
FROM bb_basketitem
WHERE idbasket = :NEW.idbasket;
In the code fragment above, which of the following represents the correlation identifier?

A) idproduct
B) bb_basketitem
C) quantity
D) :NEW.idbasket

Question 31

Which of the following indicates that the trigger is fired only once, regardless of the number of rows affected by the DML statement?

A) Statement level
B) Event level
C) DML level
D) Row level

Question 32

____ triggers refer to database triggers that are fired by Data Definition Language (DDL) statements or database system events rather than DML actions.

A) ALTER
B) CREATE
C) System
D) Instead-Of

Question 33

The statement ____ correctly deletes a trigger.

A) DEL TRIGGER trigger_name;
B) DELETE TRIGGER trigger_name;
C) REMOVE TRIGGER trigger_name;
D) DROP TRIGGER trigger_name;

Question 34

A(n) ____ trigger fires whenever the event occurs, regardless of the schema in which it occurs.

A) row level
B) system level
C) Instead-Of
D) database level

Question 35

Database system events include all of the following, except ____.

A) LOGON
B) SHUTDOWN
C) GRANT
D) STARTUP

Question 36

CREATE OR REPLACE TRIGGER logon_trg
AFTER logon ON SCHEMA
BEGIN
INSERT INTO bb_audit_logon
VALUES (USER, SYSDATE);
END;
In the code fragment above, which of the ____ statement represents the system event.

A) logon
B) INSERT
C) SYSDATE
D) AFTER

Question 37

Which of the following statements is correct?

A) If multiple triggers exist on a table, the order in which the triggers will be fired can be set.
B) A BEFORE statement level trigger will fire before a BEFORE row level trigger.
C) If you have two statement level triggers, the order in which they are fired is dependent on the order in which they were written.
D) Only one trigger can be constructed per table.

Question 38

Which of the following statements is True?

A) The body of a trigger cannot read or modify the primary, unique, or foreign key columns of a constraining table.
B) The body of a trigger cannot read or modify the primary, unique, or foreign key columns of a key-preserved table.
C) The body of a trigger cannot read or modify the primary, unique, or foreign key columns of a mutating table.
D) The body of a trigger cannot read or modify the primary, unique, or foreign key columns of a conditional table.

Question 39

A(n) ____ table is one that is involved in a join and the keys of the original table are included in the keys of the resultant join.

A) mutating
B) system
C) database
D) key-preserved

Question 40

The statement ____ recompiles the trigger named sales_trg.

A) ENABLE TRIGGER sales_trg COMPILE;
B) DROP TRIGGER sales_trg COMPILE;
C) COMPILE TRIGGER sales_trg COMPILE;
D) ALTER TRIGGER sales_trg COMPILE;

Question 41

Which trigger option will force the trigger to fire before the test_trg trigger.

A) BEFORE test_trg
B) PRECEDES test_trg
C) PRIOR test_trg
D) no option is available to control the firing order

Question 42

How can triggers be applied to accomplish referential integrity?

Question 43

A(n) ___________________________ is one that is referenced via a foreign key constraint on the table that a trigger is modifying.

Question 44

___________________________ are clauses available within a trigger to allow separate handling of different database triggering events within a single trigger.

Question 45

The values checked in the ___________________________ clause of a trigger must reference correlation identifiers.

Question 46

The ____ trigger clause allows a trigger to include multiple triggering events in a single trigger.

A) MULTIPLE
B) MULTIPLE TRIGGER
C) COMPOUND
D) COMPOUND TRIGGER

Question 47

A(n) ___________________________ is a PL/SQL block that executes in place of a DML action on a database view.

Question 48

To rebuild a database from a script, if you are using SQL Developer, open the file and click the ____________________ button.

Question 49

Discuss three critical pieces of information regarding the WHEN clause of a trigger.

Question 50

What is the difference between a mutating table and a key-preserved table?

Question 51

The ___________________________ level option is applicable only for UPDATE and DELETE events.

Question 52

A database ___________________________ is a block of PL/SQL code that runs automatically when a particular database event occurs.

Question 53

In the syntax of the CREATE TRIGGER statement, the ____________________ clause can be used to change the OLD and NEW qualifier names to something of your choice.

Question 54

The default timing of a trigger is ___________________________ level and no code is included to achieve this timing.