Lesson 1 Flashcards
1
Q
- Raw facts or figures without context (e.g., numbers, names).
- stored representation of objects
and events that have meaning and
importance in the user’s environment
A
Data
2
Q
- Processed data that has meaning and can be used for decision-making.
- data that have been processed in such a way as to increase the knowledge of the person who uses the data.
A
Information
3
Q
Converting Data in Two Ways
A
- Data in Context ( Ex. Name, In Context: Last Name)
- Summarized Data (Has Procedure and Processing)
4
Q
Give the Use of Data:
A
- To produce knowledge and have impact
5
Q
The Four Uses of Data:
A
Data - Information - Knowledge - Wisdom
6
Q
- A structured collection of related data.
- Organized according to a database model (e.g., hierarchical, relational).
- an organized collection of logically related data.
A
Database
7
Q
- data that describe the properties or characteristics of end user data, and the context of that data. (Ex. Varchar, not null)
- enable database desiners and users to understand what data exist, what the data mean, and what the fine distinctions are between seemingly similar data items.
A
Metadata
8
Q
- A software system that is used to create, maintain, and provide controlled access to user database.
- It provides a systematic method of creating, updating, storing and retrieving data in a database.
- Responsible for CRUD
A
DBMS
9
Q
Need for DBMS
A
- to build an integrated corporate database to support all requirements of the organization.
- employed stand alone systems which may cause duplication of data.
10
Q
Four Components of DBMS
A
- User
- Software
- Hardware
- Data
11
Q
Components of User:
A
- Application programmers
- End-users
- DBA
12
Q
Components of Software:
A
- DBMS
- Operating System
- Network Software
- Application Program
13
Q
Applications of DBMS:
A
- Banking
- Universities
- Airlines
- Telecommunications
14
Q
Advantage of DBMS:
A
- Reduction of Data Redundancy
- Reduction of Inconsistency
- Sharing of Data
15
Q
Disadvantage of DBMS:
A
- Cost of Software
- Cost of Hardware
- Complexity of Backup and Recovery
16
Q
Database systems comprise of complex data structures. Thus, to make the system efficient for retrieval of data and reduce the complexity of the users, developers use the method of _________ _________
A
Data Abstraction
17
Q
What are the three levels of Data Abstraction?
A
Physical Level (Internal Level), Logical Level (Conceptual), View Level (External Level)
18
Q
- Actual Physical storage structure and access paths.
- the lowest of data abstraction
- The internal view tells us what data is stored in the database and how
A
Internal Schema
19
Q
- Defines all database entities, their attributes, and their relationships
- Structure and Constraints for the entire database
A
Conceptual schema/logical level
20
Q
- only related to the data which is viewed by specific end users.
- Describes various user views
- level is nearest to the user
A
External schema/view level
21
Q
Every user should be able to access the same data but able to see a customized view of the data.
A
Goal of 3 level schema of database
22
Q
What are the Application Architecture of DBMS?
A
- Two-Tier
- Three-Tier
23
Q
This architecture was developed to deal with computing environments in which a large number of PCs, workstations, file servers, printers, database servers, Web servers, e-mail servers, and other software and equipment are connected via a network.
A
Basic Client/Server Architectures
24
Q
- This architecture is based on Client Server architecture.
- The direct communication takes place between client and server. There is no intermediate between client and server.
A
Two-tier Architecture
25
The Two-tier architecture is divided into two parts:
1. Client Application (Client Tier)
2. Database (Data Tier)
26
-Three Layers in the three-tier architecture are?
- Client Layer
- Application Layer
- Data Layer
27
also called as Presentation Layer which contains UI part of our application. This layer is used for the design purpose where data is represented to the user or input is take from the user.
Client Layer
28
acts as an interface between Client layer and Data Layer. This layer is also called the intermediary layer helps to make communication faster between client and data layer.
Application Layer
29
in this is layer is the actual database. This layer contains methods to connect with database and to perform insert, update, delete, get data from database based on the input data.
Data Layer
30
A way of organizing a collection of information pertaining to a system under investigation
Data Modelling
31
Collection of conceptual tools for describing data, data relationships, data semantics and consistency constraints.
Database Model
32
The four basic types of database models:
1. Hierarchical Database Model
2. Network Database Model
3. Relational Database Model
4. Object-Oriented Database Model
33
- The oldest form of database, developed by IBM.
- This model organizes the data in a tree structure or a parent-child relationship wherein a child may only have one parent but a parent can have several other children.
- Developed by IBM
Heirarchical Database Model
34
- was developed as an alternative to the hierarchical database.
- This model expands on the hierarchical model by providing multiple paths among segments, that is, more than one parent-child relationship.
- This model was formalized in 1971, by the Database Task Group (DBTG) of the conference on Data Systems Language.
Network Database Model
35
- based on the relational model developed by E.F. Codd.
- represents all datas in the database as simple two-dimensional tables called relations.
- In relational database, three basic operations are used to develop useful sets of data: selection, projection, and join.
Relational Database Model
36
The terms relations, attributes and domains are used frequently in relational database
1. Relation – is a table of columns and rows.
2. Attributes – are the names given to each column of the relation.
3. Domain – is the value with which the attribute will take.
37
- relatively new database model and provides an outlook for the future of database models.
- It stores and maintains objects.
- can store and access unstructured data such as pictures, videoclips, sounds more efficiently.
Object-oriented database model
38
The ability to modify a schema definition in one level without affecting a schema definition in the next higher level
Data Independence
39
it refers to immunity of an application to changes in the internal mode and access strategy.
Physical Data Independence
40
refers to immunity of the external model to changes in the conceptual model. Examples of logical data independence are addition / removal of entities.
Logical Data Independence
