Data tables: rows, columns and keys
Answers are for parents and teachers.
1
Use the table of marks: how many records, how many fields, and which pupil has the lowest English mark?
5 records, 5 fields. Pupil 3 has the lowest English mark (12).
2
Find the total of Pupil 5: 12, 14 and 20.
12 + 14 + 20 = 46.
3
Make a three-column comparison table: word-processor table, spreadsheet, database program. Write one use for each.
Word processor: a small simple table; spreadsheet: sorting and simple sums; database: much complex data with relations and higher security.
4
Design a table for a football team: five field names, a data type for each and a primary key.
Answers differ. Check sensible fields (such as player id, name, position, goals), number for numeric fields, and an id as primary key.
5
Explain in two sentences what “never repeats” means for a primary key.
No two records have the same value in that field. This lets the database tell every record apart.