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Question
What is a constraint?
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Solution
Constraint:
- The constraint is a condition applicable on a field or set of fields.
- Constraints are used to limit the type of data that can go into a table.
- This ensures the accuracy and reliability of the data in the database.
- Constraints could be either on a column level or a table level.
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| S1001 | Hariharan | Supervisor | 29000 | 12000 |
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| EMP CODE | NAME | DESIG | PAY | ALLO WANCE |
| S1001 | Hariharan | Supervisor | 29000 | 12000 |
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