"primary key=unique+null" is equal,reson?not,reason?
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Answer / prashant
Primary Key = unique + Not null
Because primary key is used to uniquely identify each row
of the table.
| Is This Answer Correct ? | 9 Yes | 0 No |
Answer / karunakar reddy s
primary key = unique and not null in a table
because primary key act as foreign key in other table, and
we can identify the records using this key. If pk has null
value how can we identify the records in the first table
| Is This Answer Correct ? | 8 Yes | 0 No |
Answer / devaraja.m
Primary key should be Unique + not null. hence
Primary key = unique+ Not null.
primary having the best role in al table, without PK we
cont identify the table itself. because it should be only
one & should not be zero.
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / sajeda
primary key = unique+ null
Because the primary key identyfi uniqe value that does not
contain nll values.
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / s.rama devi
if we create pk for any column in table. That column dont
allow the duplicate values and also not null values
| Is This Answer Correct ? | 0 Yes | 1 No |
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