What is a constraint. Types of constraints ?

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What is a constraint. Types of constraints ?..

Answer / sohail

Constraint is a restriction on table.There are two types of
constraints 1.ananymous constraint and 2.named
constraint.under named and ananymous constraints there are
1.primary key constraint
2.foreign key constraint
3. not null constraint
4. check constraint
5. unique constraint.

Is This Answer Correct ?    40 Yes 10 No

What is a constraint. Types of constraints ?..

Answer / pavani

Constraint means it is rule which you want to apply on the
table. There are two types of constraints.
1. Column Constraints: Applicable for that column only.
2. Table Constraints: Applicable for more than one column.

Column Constraints:
a. unique b. not null c. primary key d. foreign key
e.default f. check

Table constraints:
a. unique b. primary key c. foreign key d. check

Is This Answer Correct ?    26 Yes 5 No

What is a constraint. Types of constraints ?..

Answer / sujit.1551

constraint are nothing but a conditions,in other words
enforcing the business rules into the database.
types of constraits:
1)check constraint
2)unique constraint
3)primary key
4)foreign key
5)Not null
6)Default

Is This Answer Correct ?    20 Yes 3 No

What is a constraint. Types of constraints ?..

Answer / samuvel

Constraint is a restriction on table

Types:

1)Column Constraints:applicable for column level
i)unique ii) not null

2)Table constraints:applicable for table level
1)primary key ii) foreign key d. check

Is This Answer Correct ?    8 Yes 4 No

What is a constraint. Types of constraints ?..

Answer / ravi

constraints are two types
1.Rule based constraint
2.cost based constraint

Is This Answer Correct ?    0 Yes 0 No

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