Additional Programming Techniques

• Concatenation

  • The ability to join two or more strings together to form a single string
  • Concatenation uses the '+' operator to join strings together
• Files have two modes of operation - read from and write to.
• • To open a file, it must be referred to by its identifier, for example:
  • file = open("demofile.txt","r")
  • This would open the file and allow its contents to be read.
  • file = open("demofile3.txt","w")
  • This would open the file and allow it to have data written to it.
  • file = open("demofile2.txt", "a")
  • This would open the file and allow you to append it.
  • file.close()
  • This would close the file
• SQL Commands examples:

  • SELECT * FROM "personnel" WHERE "Title" = "Mr"
  • SELECT * FROM "personnel" WHERE "email address" LIKE "%com"

  Note - * stands for wildcard, which means all records. This would retrieve the following data:
• Databases use their own type of programming language. This language is known as structured query language, or SQL.
• Write an algorithm in pseudocode to:

  • store "Hello" in the variable word1
  • store "Everyone" on variable wprd2
  • concatenate word1 and word2 to store "HelloEveryone" in variable message

  word1 = "Hello"

  word2 = "Everyone"

  message= word1 + word
• Subroutine


  A named section of code that can be called and reused
• Built-in


  Premade by Python
• user-defined


  Created by the programmer
• method


  A subroutine that works on variables
• function


  A subroutine that works on any value given
• parameter


  The value/s that are passed through the brackets
• procedure


  a function that gives no value