PL/SQL Collections and Records - PL/SQL (MCQ) questions and answers

1)   Which collection exception is raised when a subscript exceeds the number of elements in a collection?
- Published on 09 Jul 15

a. VALUE_ERROR
b. COLLECTION_IS_NULL
c. SUBSCRIPT_BEYOND_COUNT
d. SUBSCRIPT_OUTSIDE_LIMIT
Answer  Explanation 

ANSWER: SUBSCRIPT_BEYOND_COUNT

Explanation:
The SUBSCRIPT_BEYOND_COUNT error is where the in-limit of a subscript was greater than that of the count of a varray or was too large for a nested table.


2)   Which collection exception is raised when a subscript designates an element that was deleted, or a nonexistent element of an associative array?
- Published on 09 Jul 15

a. NO_DATA_FOUND
b. COLLECTION_IS_NULL
c. SUBSCRIPT_BEYOND_COUNT
d. SUBSCRIPT_OUTSIDE_LIMIT
Answer  Explanation 

ANSWER: NO_DATA_FOUND

Explanation:
The NO_DATA_FOUND exception is raised when the FETCH statement is not able to find the relevant data that we have asked for.


3)   Only EXISTS can be applied to automatically null collections. If you apply another method to such collections, PL/SQL raises COLLECTION_IS_NULL.
- Published on 09 Jul 15

a. Yes
b. No
Answer  Explanation 

ANSWER: Yes

Explanation:
A built in function or procedure which is operated on collections and usually called using the dot notation is known as a collection method.


4)   Nested tables can be sparse: you can delete arbitrary elements, rather than just removing an item from the end.
- Published on 08 Jul 15

a. Yes
b. No
Answer  Explanation 

ANSWER: Yes

Explanation:
The nested tables and the varrays are the one that we need to select upon. A nested table is a dimensional array with arbitary elements.


5)   Assigning a value to a collection element can cause exceptions, such as
- Published on 08 Jul 15

a. If the subscript is NULL or is not convertible to the right datatype, PL/SQL raises the predefined exception VALUE_ERROR. Usually, the subscript must be an integer. Associative arrays can also be declared to have VARCHAR2 subscripts.
b. If the subscript refers to an uninitialized element, PL/SQL raises SUBSCRIPT_BEYOND_COUNT.
c. If the collection is atomically null, PL/SQL raises COLLECTION_IS_NULL.
d. All mentioned above
Answer  Explanation 

ANSWER: All mentioned above

Explanation:
No explanation is available for this question!


6)   Which collection types is also known as index-by tables, lets you look up elements using arbitrary numbers and strings for subscript values?
- Published on 08 Jul 15

a. Associative arrays
b. Nested tables
c. Varrays
d. None of the above
Answer  Explanation 

ANSWER: Associative arrays

Explanation:
The associative arrays helps us to look up to the elements using arbitary numbers and strings for subscript values. They are similar to hash tables.


7)   Associative arrays also known as index-by tables.
- Published on 07 Jul 15

a. True
b. False
Answer  Explanation 

ANSWER: True

Explanation:
The associative arrays helps us to look up to the elements using arbitary numbers and strings for subscript values. They are similar to hash tables.


8)   Nested tables are a good choice when
- Published on 07 Jul 15

a. The index values are not consecutive.
b. There is no set number of index values. However, a maximum limit is imposed.
c. You need to delete or update some elements, but not all the elements at once.
d. You would usually create a separate lookup table, with multiple entries for each row of the main table, and access it through join queries.
e. All mentioned above
Answer  Explanation 

ANSWER: All mentioned above

Explanation:
No explanation is available for this question!


9)   Which of the following is a group of related data items stored in fields, each with its own name and datatype?
- Published on 07 Jul 15

a. A Record
b. A Collection
c. Both A & B
d. None of the above
Answer  Explanation 

ANSWER: A Record

Explanation:
A record is a data structure which can hold items of different types.


10)   In the Restrictions on Record Inserts and Updates, which of the following are not supported?
- Published on 19 Oct 15

a. Nested record types
b. Functions that return a record
c. Record inserts and updates using the EXECUTE IMMEDIATE statement
d. All mentioned above
Answer  Explanation 

ANSWER: All mentioned above

Explanation:
The restrictions on the record are made on the DML statements. Some of the DML statements are restricted too.


1 2