Characteristic of data: size

Name:

Date:

Class:

Quick Questions

Shade in the A or B circle for each question.

1. A spreadsheet has 500 rows of student results and 6 columns. How many records does it hold?

A 6 records

B 500 records

2. A table has 1,000 records and 8 fields. Which statement is correct?

A It has 8 fields (columns) describing each record

B It has 8 records (rows) describing each field

3. Which change makes a dataset larger in size?

A Adding 2,000 new records

B Fixing a spelling mistake in one record

4. True or false: A dataset with more fields per record usually needs more storage space.

A False

B True

5. A school has 200 records in one file and 2 million records in another. Which is likely to be slower to sort and search?

A The file with 2 million records

B The file with 200 records

Match the Pairs

Draw a line connecting each item on the left to its match on the right.

Left column		Right column
1COUNTA(A2:A501)		ACounts the columns in the header row to find the number of fields in a dataset (here 8 fields)
2COLUMNS(A1:H1)		BSELECT * FROM Students WHERE Name = 'Mia'; -- scans 1,000,000 records
3A dataset with more records and more fields needs more storage space		CSize depends on both the number of records (rows) and the number of fields (columns), not just fields.
4Larger datasets can be slower to sort, search and process		D10,000 records x 20 fields = 200,000 values to store
5Size of dataset = number of fields only (8 columns)		ELarger datasets take more storage and can be slower to sort, search and process, so the speeds will not be the same.
6A dataset with 1,000,000 records will open and sort as fast as one with 50 records		FCounts the filled cells in a column to find the number of records in a dataset (here 500 rows of data)

Definitions

dataset size

Fill in the Blanks

Complete each line of code by filling in the missing parts.

=____(A2:A501)

=_______(A1:H1)

SELECT _____(*) FROM Students;

B1 = records, B2 = fields =B1_B2

SELECT * FROM Sales _____ 100;

Spot the Error

Shade in the letter of the line that contains an error.

Question 1

A SET dataset TO students

B SET records TO ROWS(dataset)

C SET fields TO ROWS(dataset)

D PRINT records, fields

Question 2

A SET records TO 100

B SET fields TO 4

C SET cells TO records + fields

D PRINT cells

Question 3

A IF records < 1000000 THEN

B PRINT "Large dataset"

C END IF

Question 4

A SET sizeKB TO 3072

B SET sizeMB TO sizeKB * 1024

C PRINT sizeMB

Question 5

A SET start TO TIME()

B SORT dataset BY surname

C SET end TO TIME()

D PRINT start - end

Answer Key

Characteristic of data: size

Section A: Quick Questions

B — 500 records

A — It has 8 fields (columns) describing each record

A — Adding 2,000 new records

B — True

A — The file with 2 million records

Section B: Match the Pairs

COUNTA(A2:A501) → Counts the filled cells in a column to find the number of records in a dataset (here 500 rows of data)

COLUMNS(A1:H1) → Counts the columns in the header row to find the number of fields in a dataset (here 8 fields)

A dataset with more records and more fields needs more storage space → 10,000 records x 20 fields = 200,000 values to store

Larger datasets can be slower to sort, search and process → SELECT * FROM Students WHERE Name = 'Mia'; -- scans 1,000,000 records

Size of dataset = number of fields only (8 columns) → Size depends on both the number of records (rows) and the number of fields (columns), not just fields.

A dataset with 1,000,000 records will open and sort as fast as one with 50 records → Larger datasets take more storage and can be slower to sort, search and process, so the speeds will not be the same.

Section C: Definitions

dataset size — How many records (rows) and fields (columns) a dataset holds, and so how much storage it needs. Larger datasets take more space and can be slower to sort, search and process.

Section D: Fill in the Blanks

=ROWS(A2:A501)

=COLUMNS(A1:H1)

SELECT COUNT(*) FROM Students;

B1 = records, B2 = fields
=B1*B2

SELECT * FROM Sales LIMIT 100;

Section E: Spot the Error

C — Fields are the columns of a dataset, not the rows. The number of fields should be found with COLUMNS(dataset). ROWS gives the number of records.

C — The number of values in a dataset is records multiplied by fields, not added. It should be records * fields. More records or fields means more data to store.

A — A dataset is large when it has MORE than a million records. The condition should use > not <, otherwise small datasets would be labelled large.

B — Converting KB to MB means dividing by 1024, because a megabyte is bigger than a kilobyte. It should be sizeKB / 1024.

D — Time taken to sort a large dataset is the end time minus the start time. start - end would give a negative number. It should be end - start.