what is Constraint? How many types of constraints in SQL ?

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what is Constraint? How many types of constraints in SQL ?..

Answer / pramod tiwari,mba-it,lpu

SQL Constraints-
Constraints are used to limit the type of data that can go
into a table.

Constraints can be specified when a table is created (with
the CREATE TABLE statement) or after the table is created
(with the ALTER TABLE statement).

We will focus on the following constraints:

•NOT NULL
•UNIQUE
•PRIMARY KEY
•FOREIGN KEY
•CHECK
•DEFAULT

Is This Answer Correct ?    9 Yes 1 No

what is Constraint? How many types of constraints in SQL ?..

Answer / nambi rajan

A constraint is a property assigned to a column or the set
of columns in a table that prevents certain types of
inconsistent data values from being placed in the columns.

There are 4 Types of Constraints.
• Entity Integrity - Primary and Unique
• Domain Integrity - Default, Check and Not Null
• Referential integrity – Foreign Key
• User-Defined Integrity - enforces some specific
business rules that do not fall into entity, domain, or
referential integrity categories

Is This Answer Correct ?    13 Yes 7 No

what is Constraint? How many types of constraints in SQL ?..

Answer / rohit nanda

A constraint is a property assigned to a column or the set
of columns in a table that prevents certain types of
inconsistent data values from being placed in the columns.

There are 4 Types of Constraints.
• Entity Integrity - Primary and Unique
• Domain Integrity - Default, Check and Not Null
• Referential integrity – Foreign Key
• User-Defined Integrity - enforces some specific

Is This Answer Correct ?    7 Yes 3 No

what is Constraint? How many types of constraints in SQL ?..

Answer / 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

what is Constraint? How many types of constraints in SQL ?..

Answer / seshu

constraint is a mechanism it is used to prevent the invalid
data entry in to the table is called constraint.
constraints are 5 types they are,

1 Primary Key Constraint
2 Foreign Key Constraint
3 Unique Constraint
4 Not Null Constraint
5 Check Constraint

Is This Answer Correct ?    5 Yes 1 No

what is Constraint? How many types of constraints in SQL ?..

Answer / sivanagireddy.k

constraints nothing but condition on column in the table by using constraint checking process or validation pprocess has been done.

constraints are 6 tyes
1.unique
2.Not null
3.Primary key
4.Check
5.Default
6.Foreign key

types of level in constraints

column level
table level

send ur queries to this mail id rsivanagireddy@gmail.com

Is This Answer Correct ?    4 Yes 0 No

what is Constraint? How many types of constraints in SQL ?..

Answer / shelly

Constraints are used to limit the type of data that goes
into a table.Constraints can be declared at the time of
creating a table or by altering the already created table.

1)Not Null
2)Unique
3)Primary Key
4)Check
5)References
6)Default

Is This Answer Correct ?    2 Yes 0 No

what is Constraint? How many types of constraints in SQL ?..

Answer / manoj kumar

Contraint is a provision to limit or enforce the data in
the sql tables. It is of five types:-
1 Primary Key Constraint
2 Foreign Key Constraint
3 Unique Constraint
4 Not Null Constraint
5 Check Constraint

Is This Answer Correct ?    7 Yes 6 No

what is Constraint? How many types of constraints in SQL ?..

Answer / krishna

constraints are use to maintain the relation between the two tables. sql contains the 5 types of constraints
1.primary key
2.foreign key
3.unique key
4.Not null
5.check

Is This Answer Correct ?    2 Yes 1 No

what is Constraint? How many types of constraints in SQL ?..

Answer / m arunachalam

Constraints are used to limit the type of data that can go
into a table.

Constraints can be specified when a table is created (with
the CREATE TABLE statement) or after the table is created
(with the ALTER TABLE statement).

We will focus on the following constraints:

NOT NULL
UNIQUE
PRIMARY KEY
FOREIGN KEY
CHECK
DEFAULT

Is This Answer Correct ?    1 Yes 0 No

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