Integrity constraints means..? how many and what are they?
- 4 Answers
- 13346 Views
- AZTEC, I also Faced
- E-Mail Answers
Answers were Sorted based on User's Feedback
Answer / firoz basha
Integrity constraint:- An IC is one which does not allow
invalid data entry into the database.
there are 3 types of Integrity constraints:
1. Entity Integrity COnstraint
primary key
unique key
Primary key does not allow null values and duplicate
values
unique key does not allow duplicate values.
unique key allows any number of null values (in case
of oracle)
unikey key allows only one null value. i.e, single null
value ( in the case of sql server 2000)
2. Domain Integrity Constraint
not null constraint
check constraint
rule constraint (in case of SQL SERVER 2000)
rule is an alternate to check constraint
3. Referential Integrity constraint
foreign key constraint
| Is This Answer Correct ? | 34 Yes | 1 No |
Integrity constraints provide a way of ensuring that
changes made to the database by authorized users do not
result in a loss of data consistency.
An integrity constraint can be any arbitrary predicate
applied to the database.
They may be costly to evaluate, so we will only consider
integrity constraints that can be tested with minimal
overhead.
Types of integrity constraints
(1) Non-null
(2) Key
(3) Referential integrity
(4) Attribute-based
(5) Tuple-based
(6) General assertions
plzz let me know if it's wrong
| Is This Answer Correct ? | 18 Yes | 9 No |
Answer / sriram s
Domain integrity enforces valid entries for a given column
by restricting the type , the format or the range of
possible values
| Is This Answer Correct ? | 6 Yes | 0 No |
Domain Integrity Constraint
//not null constraint this is not come
check constraint
//rule constraint (in case of SQL SERVER 2000)
//rule is an alternate to check constraint
only check because it is used as whole domain while all are
in row or tuple !
| Is This Answer Correct ? | 4 Yes | 0 No |
hai if any one having any project sample table structure please froward to my mail id tauseefwst@yahoo.com
What is the difference between oracle and MS Access?
Define the following terms i. Inverted List ii. Candidate Key iii. B-Tree iv. Foreign Key
What are indexes in oracle?
please tell me the informatica telecom projects interview question? like if they ask about project explanation and the difficulties and the solutions taken to solve the issues for telecom projects,e.g i am workin for a vodafone project handlin postpaid section,pls tell me wat wud be the process if i work in this ? thanks
How does non-cluster index functions?
Is it good to store images in database?
can any one tell me how i can start database testing mean what should be initial point and how i can write a query for listing page of any item thanks in advance
How to do Data integrity testing? Who does this testing (Developer or tester)?
What is a database lookup?
What is the candidate key used for?
Given a table Employee which has columns name and salary, write an SQL query to find the employee with the second highest salary.
-
Oracle (3258) - SQL Server (4518)
- MS Access (429)
- MySQL (1402)
- Postgre (483)
- Sybase (267)
- DB Architecture (141)
- DB Administration (291)
- DB Development (113)
- SQL PLSQL (3328)
- MongoDB (502)
- IBM Informix (50)
- Neo4j (82)
- InfluxDB (0)
- Apache CouchDB (44)
- Firebird (5)
- Database Management (1411)
- Databases AllOther (288)
