Integrative Programming C# - An OOP Language That Supports Data Encapsulation, Inheritance Polymorphism, and Method
Integrative Programming C# - An OOP Language That Supports Data Encapsulation, Inheritance Polymorphism, and Method
Integrative Programming C# - An OOP Language That Supports Data Encapsulation, Inheritance Polymorphism, and Method
C# - an OOP language that supports data encapsulation, inheritance polymorphism, and method
overriding; developed by Anders Hejlsberg in Microsoft (1990s)
.NET Framework – collection of tools, technologies, and languages that provides environment to build
and deploy different types of applications easily
• Operating System – controls tasks and manages system resources of the computer; manages
hardware and software resources that supports execution of .NET applications
• Common Language Runtime (CLR) – runtime environment of the .NET framework that manages
the execution of .NET code, enables debugging and exception handling, and makes programs
portable. (source code -> MSIL -> CLR JIT -> native code)
• .NET Base Class Library – contains classes and interfaces used for building applications.
• ADO .NET – provides access to relational databases and several data sources such as SQL server
and XML
• ASP .NET – Unified web development model that includes services necessary in building
enterprise-class web applications with minimum coding
o ASP .NET Forms – allows building of dynamic websites using a familiar drag-and-drop
event-driven model
o ASP .NET Web Services – extend the web infrastructure to provide means for software
to connect to other apps
o Windows Forms – contain graphical representation of any window displayed in the app
• Common Language Specification (CLS) – set of basic language features that ensures operability
between the languages in the .NET environment; a subset of Common Type System (CTS)
o CTS – a formal specification that documents how types are declared, used, and
managed so the CLR can use them
• EXE (Executable)
• DLL (Dynamic-Link-Library) – module that contains functions and data that can be used by
another module
Metadata – contained by assembly; provides information along with a complete description of methods,
types, and other resources
Manifest – included in metadata; stores identification information, public types, and a list of other
assemblies that are used in the current assembly; each has a 128-bit version number
(major.minor.build.revision)
Keywords – reserved words a programming language uses for its own use and have a special predefined meaning
to the compiler
Variable – an identifier and a memory location that stores a specific value that can be changed during program
execution.
Constant – an identifier and a memory location whose value cannot be changed during program execution.
Data Types – used to specify a set of values and their operations associated with variables or constants
• Value Types – stores value directly within the variable; holds data within its own memory allocation.
• Reference Types – do not store actual value in a variable or constant but stores address where the value is
stored
Type Conversion/ Type Casting – process of converting a value of 1 data type to another data type
• Implicit Conversion – conversion of a lower precision data type to a value of a higher precision data type.
• Explicit Conversion –converts a higher precision data type to a lower one by using cast operator ex: int
num = 25; byte b = (byte) num;
Operators – symbols that represent a specific mathematical or logical processing in programming
Expression – combination of operands (or variables) and operators that can be evaluated to a single value
Operator Precedence and Associativity – defines a set of rules indicating the order in which the operator should be
evaluated in an expression
System.Math – a class that includes several methods that perform a variety of calculations that can be used in a
program
INFORMATION MANAGEMENT
Data – raw facts; facts that have not yet been processed to reveal their meaning to the end user
Information – result of processing raw data to reveal its meaning; consists of transformed data and facilitates
decision making
Database – shared, integrated computer structure that houses a collection of the ff:
Database Management System (DBMS) – collection of programs that manages the database structure and controls
access to the data stored in database; serves as intermediary between user and database
Advantages of DBMS:
Structural Dependence – data characteristic which a change in the database schema affects data access,
requiring changes in all access programs
Structural Independence – data characteristic which a change in the database schema do not affect
data access
Data Dependence – condition in which data representation & manipulation are dependent on the
physical data storage characteristics
Data Independence – condition in which data access in unaffected by changes in the physical data
storage characteristics
Data Redundancy – exists when the same data is stored unnecessarily at different places
• Poor Data Security – Having multiple copies of data increases the chance for a copy to be
susceptible to unauthorized access
• Data Inconsistency – exists when different and conflicting versions for the same data appear in
different places
• Data-entry Errors – more likely to occur when complex entries are made in several different files
or recur frequently in one or more files
• Data Integrity Problems – existence and nonexistence of data
Data Anomalies – data abnormality which inconsistent changes have been made to a database;
develops when not all of the required changes in the redundant area are made successfully.
Database Design – focuses on hoe the database structure will be used to store and manage end-use
data
Data Modelling – first step in designing a data base; process of creating a specific data model for a
determined problem domain
Data Model – simple graphical representation of more complex real-world data structures. A model is
an abstraction of a more complex real-world object or event.
• Entity – person, place, thing or event about which data will be collected and stored
• Attribute – characteristic of ab entity
• Relationship – describes association between entities.
o One-to-one (1:1) relationship
o One-to-many (1:M) relationship
o Many-to-many (M:M) relationship
Big Data – movement to find a new and better ways to manage large amounts of web and sensor-
generated data and derive business insight from it; term was first used by John Mashey in 1990s;
Douglas Laney described these characteristics:
NoSQL – large-scale distributed database system that stores structured and unstructured data in
efficient ways.
*in the 1970s the ANSI SPARC defined a data modeling framework based on degrees of data
abstraction.
• External Model – end-user’s view of data environment; people who use the app; ER diagrams
are used to represent external views; a specific representation is called an external schema
• Conceptual Model – represents a global view of the entire database by the entire organization;
conceptual schema is the basis for the identification and high-level description of main data
objects
• Internal Model – representation of database as seen by the DBMS; requires designer to match
conceptual model’s characteristics and constraints; internal schema depicts a specific
representation of an internal model
• Physical Model – operates at lowest level of abstraction; describing how data is saved on
storage media.