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what is primary key,unique key, foreign key? can u teach me
in simple language?
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Answer Posted / rahul patil
PRIMARY key is one which uniquely identifies a row in the
table.
It does not has any null value entry.It can be formed by
using one or more fields of the table.If more fields are
used then the key is known as COMPOSITE key
| Is This Answer Correct ? | 6 Yes | 5 No |
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