2.2

Question 1

constant

Answer 1

a value that does not change while the program is desinged

Question 2

variable

Answer 2

a value stored in memory that can change while the program is running

Question 3

casting

Answer 3

converting a variable from one data type to another

Question 4

string manipulation

Answer 4

changing a string through collecting the length of the string (e.g. ‘.length’)

Question 5

what are the stages to write data to a file

Answer 5

• open the file for creating, overwriting or appendding a file
• write the data to a file
• close the file

Question 6

what are the stages to reading data in a file

Answer 6

• open the file for reading data
• assign a boolean variable to “false”
• read the data from the file to check if the data matched is what is beign looked for
• close the file

Question 7

how do you open a file name

Answer 7

e.g. “file = open(sample.txt)”

Question 8

what commands are used in SQL

Answer 8

• SELECT, which fields to be returned - can be used to indicate fields
• FROM, which table - databases can have more than one table, each with their own unique name
• WHERE, records meet a condition (* is used as a wild card)

Question 9

what is an array

Answer 9

• a static number of related data items that are stored together in the same memory space
• each data item has the same data type
• the particular item (element) is found using its index

Question 10

what is a sub-routine

Answer 10

• larger programs that are developed as a set of sub-programs

Question 11

why are sub-routines useful

Answer 11

• structuring codes into sub-programs makes the code easier to read and debug
• functions return values and create reusable program components

Question 12

what are procedures

Answer 12

• they create a modular structure to program making it easier to read
• each sub-program can easily be tested
• sub-programs can be saved into libraries and reused in other programs