Database - The Relational Model and Normalization - Discussion

Discussion Forum : The Relational Model and Normalization - General Questions (Q.No. 14)
14.
A key:
must always be composed of two or more columns.
can only be one column.
identifies a row.
identifies a column.
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
16 comments Page 2 of 2.

Divye said:   1 decade ago
A key can be constraint on a row as its defination states so.

Kamlesh said:   1 decade ago
Def on Key: A key is one or more data attributes that uniquely identify an entity. In a physical database a key would be formed of one or more table columns whose value(s) uniquely identifies a row within a relational table.

Charu said:   1 decade ago
Key is a constraint which is applied on a column not on the row.

Harshal said:   1 decade ago
Redcords are of particular table are stored as in rows and if we have a key then it ifentifies a that particular row in which entered key belongs.

Pratibha said:   1 decade ago
option:D is correct.

Nishith said:   1 decade ago
How a row?

A key is a constraint which is applied on a column.


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