CBSE · 083Class XII · 2023Section E1 mark
Question 34(1)
30 March 2023 · Computer Science (083)
The school has asked their estate manager Mr. Rahul to maintain the data of all the labs in a table LAB. Rahul has created the table and entered data of 5 labs.
Table : LAB
| LABNO | LAB_NAME | INCHARGE | CAPACITY | FLOOR |
|---|---|---|---|---|
| L001 | COMPUTER | VIJAY | 30 | II |
| L002 | CHEMISTRY | HARSH | 20 | I |
| L003 | BIOLOGY | SONIA | 20 | I |
| L004 | ENGLISH | GAGAN | 40 | II |
| L005 | MATHS | MEENU | 35 | III |
(i) Identify the columns which can be considered as Candidate keys.
Answer
Candidate keys : LABNO and LAB_NAME
Explanation
Both LABNO and LAB_NAME contain unique, non-null values for every row, so either could serve as the primary key — that makes both candidate keys.