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Old Monday, April 21, 2008
Syed Zaffar Iqbal's Avatar
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Post Introduction to Programmin Languages

Introduction to Programming Languages
Compiled By: Syed Zaffar Iqbal
Language
Language is a way of communication. A characteristic style of speech or writing that interacts between two mediums that is user and machine. A set of characters convention and rules that is used for conveying information is called Language.

Program
A well-define set of instructions given to computer is called program. A computer program is written in a programming language.

Programming
Programming is the process of writing computer based programs or software. Creating of a computer program is called programming. The steps are
Preparing the necessary documentation.
Writing the program logic.
Developing the program.
Assembling, compiling or interpreting the program.
Testing and debugging the program.

Programmer
A programmer is person who does computer programming & develops computer software are programmer.

PROGRAMMING LANGUAGE
A set of words and symbols used to write a program is called programming language. The programming languages are used to write computer program. A programming language is a means of communication between a user and computer. In other words programming language is a complex synthetic mechanism which provides some special features to build/develop any program/software are called programming language. All the computer software is written in a special type of computer software called the programming languages.

Types of Programming Languages
There are two major types of computer programming languages i.e. Low Level Languages and High Level Languages.


LOW LEVEL LANGUAGES
A low level language that is very closer to the computer hardware. The term low level means closeness to the way in which the machine has been built. Low levels are machine oriented languages and required extensive knowledge of computer hardware and its configuration. The low level languages are divided into machine language and assembly language.

Machine Language
A type of language in which instructions are written in binary form called machine language. It is the only language that is directly understood by the computer. It doesn’t need any translator program. We also called it machine code and it is written as string of binary (1s or 0s). It is at the native language of the computer. A program written in machine language can be executed very fast by computer. The computer does not need any translator to understand this language. The programs written in machine language are machine-dependent. Every computer has its own machine language. A program instruction may be like this 100110101. It is not an easy language for you to learn because of its difficult cods and it is also difficult understand. It is efficient for the computer but very inefficient for the programmers.

Assembly Language
A programming language that is one step away from machine language means to say that it is first step to improve the programming structure. In assembly language, machine instructions are replaced with English-like word known as mnemonics. It is pronounced as Ne-Monics. Assembly language is mostly used for writing system software. Programs written in assembly language are easier to write and modify than machine language. Assembly language and a translator program is requiring translating the assembly language into machine language. The translator program is called “assembler”.


HIGH LEVEL LANGUAGES
High-level languages are programming languages that are more user friendly, to some extent platform to independent and abstract form low-level languages. In high-level languages we can’t directly interact with the hardware. Assembly and machine language require deep knowledge of computer hardware. Where as in high-level languages you have to know only the instruction in English words and logic of the problem irrespective of the type of computer you are using. High level languages are simple languages that use English and mathematical symbols like +,-,*, / etc for its program creation. In high level languages we use compiler or interpreted to translating our program. The high-level languages enable to the programmer to write the program the English words, but these English words cannot be understand by the computer, so special types of translators (compilers, interpreters) are required that convert the high-level language program into the machine readable format (machinery language program) that can be read by the computer without any further translation. There are different types of the high-level languages, such as: BASIC, FORTRAN, COBOL, PL/1, VB, Pascal, ALGOL, Ada, C language etc.



Commonly Used High-Level Languages

 COBOL: stands for COmmon Business Oriented Language; it is specially designed for business applications.
 BASIC: stands for Beginner All Purpose Symbolic Instruction Code. It was used mainly by students to use the computer for solving simple problems.
 FORTRAN: stands for FORmula TRANslation. It has very powerful mathematical capabilities.
 Pascal: it is used for both sciencetific and business applications.
 Java: it provide strong feature for network programming.
 C/C++: it is used to write system software and application software.

Characteristic/Advantages of High-Level Languages
Some important Characteristic/Advantages of high-level languages are as follows:
Easy to Learn: High-level Languages are closer to human languages and far from machine language. These are English like language and are easier to learn.
Easy Error Detection: High-level languages are easy to read and modify. It makes it easy to find error in programs written in these languages.
Standardized Syntax: The syntaxes of high-level languages are standardized. These languages described a well-defined way of writing programs. Different organizations work to determine standard syntax of these languages. An important organization is American National Standard Institute (ANSI).
Deep Hardware Knowledge not Required: These languages do not require deep knowledge of hardware or machine architecture. A programmer can write efficient programs without an in-depth knowledge of hardware. The programmer can concentrate on solving the problem rather than concerning the human-machine interaction.
Machine Independence: High-level languages provide machine independence. It means that the programs written in high level languages can be executed on different types of computers. For example, a program written in C can be executed on Intel processor and Motorola processor with a little modification.
More Programmers: Programming in low-level language is very difficult. But high-level languages are easy to learn. It encourages more people to learn these languages. So many programmers of high-level languages are available.
Shorter Programs: Programs written in high-level languages are shorter than low-level languages. One instruction of high-level languages is equivalent to many instructions of low-level language.

STRUCTURED PROGRAMMING LANGUAGE
In structured programming languages, the entire logic of the program is divided into number of smaller modules or function. Each module is a piece of code that implements a different functionality. The main module calls other modules when they are needed execute. It is a modular method of written programs. It is an easy and simple technique to write program. The programs written in these languages are easy to understand, modify and debug. There is also less possibility of errors in the programs.

UNSTRUCTURED PROGRAMMING LANGUAGE
In unstructured programming languages, the entire logic of the program is implemented in a single module of function. The programs written in these languages are error prone, difficult to understand, modify and debug.

LANGUAGE TRANSLATORS (Language Processor)
Computer understands only machine language. A program written in high-level or assembly language cannot be run on a computer directly. It must be converted into machine language before execution. Language processor or translator is software that converts these programs into machine language. Every computer language has its own translator. It is a special type of the software use for converting the software from one language to another language. All the computer software is written in a special type of computer software called the programming languages. There are three types of the processors or translators:
 Assembler  Interpreter  Compiler

Assembler
A program that translates assembly language instructions into machine language instructions is called assembler. Assembly language is translated in to machine language by a piece of software is called assembler.

Interpreter
An interpreter is a program that converts one statement of a program into machine at one time. It executes a statement before translating the next statement of source program. If there is an error in the statement, interpreter stops working and display an error message. The advantage of interpreter over compiler is that an error is found immediately. So the programmer can correct errors during program development. The disadvantage of interpreter is that it is not very efficient. The interpreter does not produce an object program. It must convert the program each time it is executed. So we can say that interpreter can check the program line by line. Java, Basic and Visual basic uses interpreter.

Compiler
A compiler is a program that converts the instruction of a high-level language into machine language as a whole. A program written in high-level language is called source program. The compiler converts the source program into machine code. The machine code program is known as object program. The object program can executed many times.

Source Program ----------------- Computer --------------- Object Program

The compiler checks each statement in the source program and generates machine instructions. Compiler also checks syntax errors in program. A source program containing an error cannot be compiled. A compiler can translate the programs of only those languages for which it is written. For example, C compiler can translate only those programs that are written in C language.
Compiler can first check the entire program if there are some errors in the whole program than it can show all the possible errors in the program. It means compiler can check the program at whole. C, C++, COBOL and FORTRAN are uses interpreter.

Linker: a program that combines the object program with additional library files is known as linker. It is a part of compiler. It combines object program and library files and saves the final machine language program as executable file. The extensive of executable files is .exe.

Source code
Source code is a computer program written in a high-level programming language like C, C++, Visual Basic or Java. Computer cannot understand the statements of high-level language. The source code cannot be executed by directly. It is converted into machine code and then executed.

Object Code
An object code is the program that is translated by a language processor. It is also called machine code. Computer understands object code directly.

TESTING AND DEBUGGING
When any software company completes any software, after completion of the same testing department can check all the software according to the user requirements to make software free of errors. For this purposes he can check/test all the software thoroughly, separately all modules of the software, and if found any error in the software then correct them. Phase in which team checks software called Testing and the phase where a team correct error is called Debugging. So this all procedure called testing and debugging.

ERROR: An error is incorrectly written code, usually intentional there are three types of errors.
 Syntax Errors  Logical Errors  Run-Time Errors

SYNTAX ERRORS: A collection of rules for writing program in a programming language is called as syntax. Syntax error is a type of error that occurs when an invalid statement is written in program. Syntax means any spelling error or any typing error. Because programmer can mention wrong spelling for the same code so it calls syntax error. Syntax errors are detected by compiler. A program containing syntax error cannot be compiled successfully. There can be many causes of syntax errors. Some important causes are as follows:
The statement terminator is missing at the end of statement.
A variable is used without declaration.
Any of the delimiters is missing.
Example: Typing print instead of printf is an example of syntax error.

LOGICAL ERRORS: A type of error that occurs due to poor logic of the programmer is called as logical error. A logical error occurs when the program follows a faulty algorithm. A statement with logical error may produce unexpected and wrong result. If programmer make any program and then compile them if there are not any error in the program it can run correct without any error but the result can not show’s correctly according to programmer desire then it calls logical error.
Example: If a programmer writes a wrong formula to calculate the result or if a programmer use wrong loop condition or if a programmer use wrong if condition, these are the examples of logical errors.

RUN TIME ERRORS: A type of error that occurs during the execution of program is called run-time error. It is caused when a statement directs the computer to execute an illegal operation such as dividing a number by zero. The run-time errors are detected and displayed by the computer during execution. Run-time errors are normally caused due to wrong input from the user. The computer stops executing the program and displays error message if a runtime error occurs.
Example: The user may ask the program to open a file that does not exist. Similarly or the user may enter wrong type of data are the examples of run-time errors.

MOST DIFFICULT ERROR
The most difficult type of error is logical error for the following reasons:
o It cannot detect by the compiler.
o It does not crash the program. That is why it is difficult to detect.
o The user needs to review the whole program to find out logical error(s).
o It may take a lot of time for detecting logical error.

BUG: A small Programming error is called Bug. A computer bug is an error, fault, flaw, mistake or failure in a computer program that prevents (stop) it from working correctly or produces an incorrect result. Bugs arise from mistakes and errors made by programmer.

DEBUGGING: Debugging is a methodical (logical) process of finding and reducing the number of bugs. The process of finding and removing bugs is known as debugging.

Prepared By: Syed Zaffar Iqbal
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Old Tuesday, January 01, 2013
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Default Oracle (bbsydp) paper

 Circle the correct option
 There are 50 Multiple Choice Questions. Each question has one correct answer. Circle your answers clearly on the MCQ.
 Each correct answer will earn you one mark. No penalty will be given for incorrect answers.
 Do not write any other thing only circle the correct MCQ answer.
SECTION ONE
1. The “g” in Oracle 10g or 11g stands for _________
a. Gird
b. Gateway
c. Guide
2. .RDF extension of _____________
a. Report developer
b. Form Developer
c. Graph developer
3. The process of converting complex data structures into simple, stable data structures is referred to as:
a. Normalization
b. De Normalization
c. process modeling
4. When Button Pressed is type of ______________
a. Trigger
b. Alert
c. Message
5. Which SQL statement is used to extract data from a database?
a. SELECT
b. GET
c. OPEN
d. EXTRACT
6. Which SQL statement is used to update data in a database?
a. SAVE
b. MODIFY
c. UPDATE
d. SAVE AS
7. Display item of form developer object is used for _______________
a. Input purpose
b. Selection Purpose
c. Only show value
8. Which SQL statement is used to delete data from a database?
a. DELETE
b. TRUNCATE
c. REMOVE
9. Which SQL statement is used to insert new data in a database?
a. ADD RECORD
b. ADD NEW
c. INSERT
d. INSERT NEW
10. ________ is heart of any software
a. Reports
b. Layout
c. Graph
11. With SQL, how do you select a column named "ename" from a table named "EMP"?
a. SELECT Emp.ename
b. EXTRACT ename FROM Emp
c. SELECT ename FROM ename
12. With SQL, how do you select all the columns from a table named "Student"?
a. SELECT [all] FROM Student
b. SELECT Student
c. SELECT * FROM Student
13. Executable file of oracle form developer is ______________
a. .sql
b. .fmb
c. .fmx
d. None of above
14. With SQL, how do you select all the records from a table named "Student" where the value of the column "FirstName" starts with an "a"?
a. SELECT * FROM Student WHERE FirstName LIKE '%a'
b. SELECT * FROM Student WHERE FirstName='a'
c. SELECT * FROM Student WHERE FirstName LIKE 'a%'
15. Lov stands for __________
a. List of values
b. Link of values
c. None of above
16. The process of combining two tables in a relational database is known as a --------------
a. Join
b. Combine
c. Relate
17. There are four major component of form developer.
a) True
b) False
18. DCL stands for ____________________
a. Data computer language
b. Data control language
c. Disk control language
19. The UNIQUE and FOREIGN keys cannot have NULL values (False)
a. Ture
b. False
20. Which SQL keyword is used to sort the result-set?
a. ORDER
b. SORT
c. SORT BY
d. ORDER BY
21. <=,>=,<> are example of _____________ of Operator
a. Arithmetic Operator
b. Relational Operator
c. Logical Operator
22. With SQL, how can you insert a new record into the "Student" table?
a. INSERT ('Saleem', 'Ali') INTO Student
b. INSERT VALUES ('Saleem', 'Ali') INTO Student
c. INSERT INTO Persons VALUES ('Saleem', 'Ali')
23. Oralce is ______________ types of language
a. RDBMS
b. DBMS
c. Oracle is not database
24. The person who is having central control over data and programs accessing that data__________
a. Developer
b. DBA
c. Programmer
25. A tuple is also known as a(n) ___________________________ .
a. Column
b. Row
c. Table
26. A table can have more than one primary key.
a. True
b. False
27. A foreign key must :
a. Be defined in all tables in the database.
b. Be numeric.
c. Match the field value of a primary key in a related table.
d. Be unique.
28. PL stands for ______________________
a) Procedure Language
b) Programming Language
c) None of these
29. Which SQL command would you use to define the primary key for a new table called 'Employee' with the primary column to be 'empid'?
a. ADD TABLE Employee ADD PRIMARY KEY (empid)
b. ATTACH TABLE Employee ADD PRIMARY KEY (empid)
c. ADD TABLE Employee ATTACH PRIMARY KEY (empid)
d. ALTER TABLE Employee ADD PRIMARY KEY (empid)
30. Which command is used to create new user?
a. Alter user
b. Create User
c. Identified by user
31. The name of a table can be changed with Alter command.
a. True
b. False
32. Only one------------------------Key can be created for an each table
a. Primary key
b. Foreign key
c. Unique
33. Three DDL commands:
a) CREATE, ALTER, DELETE
b) INSERT, UPDATE, DELETE
c) CREATE, UPDATE, DROP
d) CREATE, ALTER, DROP
34. A table once created can be dropped.
a. True
b. False
35. Which command displays the SQL command in the SQL buffer, and then executes it?
a) Get
b) Run
c) Save
36. What operator performs pattern matching?
a) LIKE operator
b) 2) Plus Operator
c) Greater Operator
37. Which command is used to store or save the query?
a) Save
b) Store
c) Get
38. What command is used to create a table?
a) Create Table
b) Create Database Table
c) Table Create
39. Loops and branching in PL/SQL include three variations. Which one is not legal?
a. Loop
b. Do Loop
c. For Loop
d. While Loop
40. The common SQL*Plus command which causes the results of PL/SQL statements to be displayed is
a. Set serveroutput on
b. Severouput enable
c. Set serveroutput off
41. Foreign key get the references from_____________
a. Unique Key
b. Not Null
c. Primary key
42. PL/SQL blocks contain __________________sections
a. One
b. Two
c. Three
43. _____________section is the first section of the PL/SQL block.
a. Declare
b. Begin
c. End;
44. The “i” in Oracle 8i stands for “improved”
a. False
b. True
45. PB is prefix of __________ object
a. Bush Button
b. Combo box
c. Display Item
46. There are _________ types of reports provide by report builder
a. Four
b. Six
c. None of above
47. Alert box show the ______________ on screen
a. Message
b. Error
c. None of above
48. Which Statement is used to show structure of specific table?
a) Describe Statement
b) Clear screen Statement
c) Select Statement
49. Contacting (||) Operator is used to combine ___________ value in a single value.
a) String
b) Numeric
c) Picture
50. Extension of Menu file is ____________
a. .MMB
b. FMX
c. RDF


SECTION TWO
Q2. Write a program in Pl/Sql print Numbers (1 to 10)
Note: By Using any loop statement.
Q3. Create a table Name ”Student” with column (Roll,Sname,Course,Address)
Note: Add Primary key in Roll, Not null in course)
Q4. Insert record into Student.
Q5. Add new column (Contact) in Student.
Q6. Delete all records from Student table.
Q7. What does following terms stands for:
1. DDL __________________________________________________ _______________________
2. DML_______________________________________________ ___________________________
3. DBMS______________________________________________ ____________________________
4. DCL_______________________________________________ _______________________________
5. RDBMS_____________________________________________ _______________________________
6. Trunc_____________________________________________ ________________________________
7. SQL __________________________________________________ ____________________________
8. ANSI______________________________________________ ________________________________
9. DBA_______________________________________________ ________________________________
10. BBSYDP____________________________________________ ________________________________
Q8. Write the following Quires :
a) Display the names and hiredate of all employees.
b) Write sql query to show those employees that have a name starting with J, K, L, or M.
c) List the employee details whose salary is greater than 2000
d) Show the structure of Department table. And Show all Records.
e) Create a query to display employee name and salary of all employees who earns more than 4000.
f) Select initcap(‘BENAZIR BHUTTO SHAHEED YOUTH DEVELOPMENT PROGRAM”) from dual
g) Show the unique job from employee table.
h) Display all records of employees where the third char of the name is an o.


HAVE A NICE DAY……..
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Default need of cultural scholar ship past papers cat computer scinec

Dear All
i have need of past papers of cultural scholarship for cat computer science if any have kindly share
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