Week1 - Introduction to Databases / Analyze

The questions can come in any order, so make sure you are selecting right option for all questions.

Q - Database has many unique characteristic. Look at the characteristic and identify the whether the following statement is true or false.

1. Data base is shared among different organizations with the same format - Shared

TRUE

2. No two data items in the database should represent the same real world entity - Non redundancy

TRUE

3. Data in the database cannot exist permanently - Persistency

FALSE

4. Data in the database is generally granted access to all the default users - Security

FALSE

5. If level 1 schema changes then all the other schemas have to be changed accordingly - Independence

FALSE

Q - Label the following block diagram of simplified database system environment.

Q0 (Block 1)

Application Programs/Queries

Q1 (Block 2)

Software to Process Queries/Programs

Q2 (Block 3)

Software to Access Stored Data

Q3 (Block 4)

Stored Database Definition (Meta-Data)

Q4 (Block 5)

Stored Database

Q - File processing system has many disadvantages. Look at the following statements and identify the disadvantage.

1. In file processing, every user group will maintain its own files for handling its data-processing applications.

(a) Data redundancy and inconsistency

2. File processing environments do not allow needed data to be retrieved in a convenient and efficient manner.

(b) Difficulty in accessing the data

3. As all the data are scattered in various files, and files may be in different formats, writing new applications programs to retrieve the appropriate data is difficult.

(c) Data isolation

4. Atomic means the transaction must happen in its entirety or not at all. It is difficult to ensure atomicity in a conventional file processing system.

(d) Atomicity problems

5. The data values stored in the database must satisfy certain types of inconsistency.

(e)Integrity problems