Database test
- Question 1. Advantages of database:
-
Reduce redundancy, consistency and integrity of data.
-
Attributes are described in many different data files.
-
Ability to appear inconsistent and inconsistent data.
-
Appeared anomalous information.
-
- Question 2. Anomalous information may:
-
Consistent data and integrity.
-
There are no conflicting information.
-
Lack of information in storage.
-
Reflect the true objective data.
-
- Question 3. Users can access:
-
The whole database
-
Limit
-
Part of the database
-
Depends on access
-
- Question 4. The DBMS (DataBase Management System) database management system is:
-
Software system controls access strategies and database storage organizations.
-
Create data structure corresponding to data model.
-
Update, insert, remove or modify file level data.
-
Ensure safety, data security and data integrity.
-
- Question 5. Characteristics of a data model:
-
Users have access at anytime, anywhere.
-
Stability, simplicity, need to check for redundancy, symmetry and have a solid theoretical basis.
-
Simple and unstructured data representation.
-
Simple data model.
-
- Question 6. When manipulating data manipulation language on hierarchical database:
-
There is a high probability of information volatility.
-
Ensure data independence
-
Ensure data integrity.
-
Ensure stability
-
- Question 7. The structural characteristics of the network model are:
-
Contains one - one, one - many and many - many links.
-
Contains one-to-one and one-to-many links.
-
Contains multiple links - one and one - many.
-
- Question 8. In the network database, when adding new records:
-
Ensure consistency and integrity of data.
-
Excess information.
-
Consistency and integrity of data is not guaranteed.
-
Conflict of information.
-
- Question 9. In the relational database model:
-
The order of the columns is not important.
-
The order of the rows is not important.
-
The order of the rows is important.
-
The order of columns is important.
-
- Question 10. X is a subset of attributes, symbol X Ω, when and only if:
-
For every attribute of Ω
-
If A Ω, deduce A X.
-
For every attribute of Ω, is also the property of X
-
For every attribute of X is also the attribute of Ω
-
- Question 11. X and Y are any two subsets of Ω. Then XY means:
-
When the argument is the same, the function has many values.
-
(r, s R) ((a X) (r (a) = s (a)) deduce (b Y) (r (b) = s (b))).
-
A value of Y is determined by a value of X.
-
(r, s R) (r (X) = s (X)) deduce r (Y) = s (Y)
-
- Question 12. Which of the following dependencies is fully dependent:
-
(Invoice number, customer code) Customer name
-
(ID card number, employee code) Working process
-
(Order number, class code) Student's full name.
-
(Newspaper code, customer code) Price quote
-
- Question 13. Which type of standard, name and address attributes does the relationship contain?
-
Standard format 2NF
-
Standard form 1NF, not 2NF
-
Standard 3NF format
-
Standard 2NF form, not 3NF
-
You should read it
- Test about database security P8
- Test of database security P10
- Test of database security P9
- Test on database security P6
- Test about database security P13
- Test on database security P7
- Test about database security P12
- Test about database security P11
- Test about database security P5
- How to Hack a Database
- Test on database security P4
- Use the ALTER DATABASE command to migrate DATABASE in SQL Server
Maybe you are interested
How to get data from web into Excel
What information does a VPN hide? How does it protect your data?
How to transfer data between 2 Google Drive accounts
6 Data Collecting Apps You Need to Delete for Better Privacy
How to master numerical data in Google Sheets with the AVERAGE function
How to delete white space in a table in Word - Appears right below the data