Additional Programming Techniques

• What is an array in programming?

  A static data structure for fixed data elements
• What must each data element in an array be?

  Of the same data type
• What is the index in an array?

  A number indicating the position of elements
• What index does the first element in an array have?

  0
• How can you traverse an array in programming?

  Using a for loop
• Can you insert new values into an array?

  No, the size is fixed
• What happens when you overwrite the fourth element in an array?

  It changes to the new value
• How do you delete a value in an array?

  Overwrite it with a blank
• What is needed to search through a large array?

  A for loop to check each element
• What is a two-dimensional array?

  An array with multiple rows and columns
• How is indexing done in a two-dimensional array?

  Using two index values for row and column
• How do you print a specific data element in a two-dimensional array?

  Use the index number
• How do you search for a specific value in a two-dimensional array?

  Use two for loops
• What can records store that arrays cannot?

  Data of different data types
• What is each piece of information in a record called?

  A field
• What is a key field in a record?

  Unique data identifying each record
• Why is Student ID a good key field?

  No two students can have the same ID
• What does SQL stand for?

  Structured Query Language
• What is the purpose of SQL?

  To search for data in a database
• What is the format of an SQL statement?

  SELECT field1 FROM table WHERE criteria
• What does the * symbol represent in SQL?

  All fields
• Write an SQL statement to select all fields for cars that are grey or blue.

  SELECT * FROM Cars WHERE Colour = "grey" OR Colour = "blue"
• Write an SQL statement to display all fields for cars that are 10 years old or less.

  SELECT * FROM Cars WHERE Age <= 10
• What are the differences between a 1D array, 2D array, and record?

  • 1D Array: Fixed size, same data type
  • 2D Array: Multiple rows and columns, same data type
  • Record: Different data types, contains fields
• What are the steps to manipulate arrays in pseudo code?

  1. Traverse: Use a for loop
  2. Insert: Change existing values
  3. Delete: Overwrite with blank
  4. Search: Use a for loop for specific value