what is Constraint? How many types of constraints in SQL ?
Answer Posted / ramesh.n
constraints are the restrictions or limitations that are
being imposed on the columns of a table to validate the data
either for insertion or updation constraints can be imposed
either during the process of table creation of a level.
There are 8 types of constraints
1.unique
2.Not null
3.Primary key
4.Check
5.Default
6.Foreign key
7.composite primary key
8.composite unique key
| Is This Answer Correct ? | 6 Yes | 2 No |
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