CBSE Guess > Papers > Important Questions > Class XII > 2013 > Multimedia & Web Technology > Multimedia & Web Technology - by Mr. Amrit Chhetri
CBSE CLASS XII
Multimedia & Web Technology
Q. 4. What are the use of Memo and Auto Data type?
ANSWERE-Q1.4: The Auto is used to create the sequence of an auto-generated numbers whereas Memo is used to store the binary data.
Q. 5. What is Degree of a Table?
ANSWER-Q1.5: The number of the columns or attributes in a table is called Degree. A attribute is also called Column. So, it is also a count of the attributes.
Q. 6. What is a Cardinality of Relation?
ANSWER-Q1.6: The number of tuples in a table is called Cardinality. A tuple is also called Row. So, it is also a count of the rows.
Q. 7. What are two the differences between Number and Date types?
ANSWER-Q1.7: Two differences between Number and Date types are give below:-
| Number | Date |
| It allows to store any numeric values. | It allows to store Date values. It can't hold more than 8 digits. |
| It can store only number type values and does not allow the character values. | It can store system date, containing date and time information. |
Q. 8. What are two the different types of relations among the tables?
ANSWER-Q1.8:
Any two out of the following relations can exist between two tables:
- One- To-One
- One-To-Many
- Many-To-Many
Q. 9. What are the three differences between Alternate and Foreign Keys?
ANSWER-Q1.9:
Three differences between Alternate and Foreign Keys are give below:-
| Alternate key | Foreign key |
| It is a candidate key that is not the primary key. | It is key in table which is a primary key in another table. It is used to link the related table. |
| It is one out of the set of candidate keys. | It is always s primary key for the first table. |
| A key that can be used as a unique identifier for the record sets. | It does not uniquely identify the rows in the table. |
Q. 10. What are the two differences between Candidate and Primary Keys?
ANSWER-Q1.10:
Two differences between Candidate and Primary are give below:-
| Candidate Key | Primary key |
| The attributes or columns of a table that can serve as the Primary Key. | It is one or more than one attributes which can identify the unique records in a table. |
| It can't become a Foreign Key in another table. | It is the candidate for a Foreign Key in another table. |
Submitted By : Mr. Amrit Chhetri
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