A primary key must be 1. unique and cannot be null 2. unique and can be...
A primary key must be
1. unique and cannot be null
2. unique and can be null
3. duplicated and cannot be null
4. duplicated and can be null
Homework Answers
| A primary key must be unique and cannot be null |
| A primary key is a field used to identify records uniquely in a database. |
| A primary key must always have a value and cannot be left blank. |
| Option 1 is correct |
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A primary key must be
1. unique and cannot be null
2. unique and can be...
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