O-LevelComputer ScienceDatabases2210/22 · May/June 2020 · Q66 Marks

A database table, JUICE, is used to keep a record of cartons of fresh fruit juice available for sale. | Juice code | Fruit 1 | Fruit 2 | Size | Volume (ml) | Stock level | |---|---|---|---|---|---| | LMO10 | Mango | Orange | Large | 1000 | 18 | | MOO05 | Orange | Orange | Medium | 500 | 8 | | SAM02 | Apple | Mango | Small | 200 | 25 | | SAA02 | Apple | Apple | Small | 200 | 50 | | SPP02 | Pineapple | Pineapple | Small | 200 | 10 | | MMM05 | Mango | Mango | Medium | 500 | 12 | | LMM10 | Mango | Mango | Large | 1000 | 5 | | MGG05 | Guava | Guava | Medium | 500 | 5 | | SMO02 | Mango | Orange | Small | 200 | 7 | | MOP05 | Orange | Pineapple | Medium | 500 | 12 | | LAA10 | Apple | Apple | Large | 1000 | 32 | | SGO02 | Guava | Orange | Small | 200 | 10 | | LPP10 | Pineapple | Pineapple | Large | 1000 | 3 | | LOO10 | Orange | Orange | Large | 1000 | 25 | | SOO02 | Orange | Orange | Small | 200 | 40 |

(a)Identify a suitable field to use as the primary key. State a reason for your choice. Field Reason[2]
(b)Complete the query-by-example grid to display only the stock level and size of all cartons containing only apple juice. Field: Table: Sort: Show: Criteria: or:[4]

Mark scheme

Marking points from the official mark scheme (May/June 2020). The mark or mark type is shown in brackets.

[1] Field: Juice code
[1] Reason: only unique identifier
[1] Field row correct (Fruit 1, Fruit 2, Size, Stock level)
[1] Table row correct (JUICE for all relevant columns)
[1] Show row correct ([ ] for Fruit 1/Fruit 2, [x] for Size/Stock level)
[1] Criteria row correct (="Apple" for Fruit 1 and Fruit 2, empty for Size/Stock level)

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