Programming Techniques

Programming Techniques

1. Variables can change over whilst a program runs. Constants cannot change whilst the program runs.

2. The "=" operator can be used in a variety of ways. i.e. Assigning values or Comparing values.

3. Casting is the identifying of a value and assigning a datatype.

4. 2-Dimensional Arrays are Tables. Single dimensions are Rows or Columns in an Array.

5. Modular code allows code to be reused and allows work to be divided among programmers.

6. Variables

   • Input, Output, Assignment, Pseudocode, Flowchart, Identifier, Variable, Constant, Concatenation, Memory-location, Parameter,

7. SQL

   • SELECT, FROM, WHERE, And, Or,
     • A database in a library has records of BookID, BookTitle, Author, Genre, etc... called "books". This is 1 dimension. The 2nd dimension is different books. I want to find all book titles by an author "X" that are of the genre "Crime".
       • SELECT BookTitle FROM books WHERE Author = X and Genre = Crime

8. String Manipulation

   • LEN (Length), SubString, Upper, Lower, CHR, ASC, Concatenate (Joining together)

9. Datatypes

   • Boolean = True/False, String, Float = numbers (decimal), Integer = Whole numbers (not decimal)

10. Loops

    • while <condition>, for <>