Update operations in dbms - insert operation, Database Management System

Assignment Help:

Update Operations and Dealing with Constraint Violations

There are three basic operations to be executes on relations:

  • Insertion
  • Deletion
  • Update

The INSERT Operation:

The insert operation permits us to insert a new tuple in a relation. When we try to insert a new record, then any of the following four types of constraints can be violated:

 

  • Key constraint: If the value of the key attribute in new tuple t is the similar as in the existing tuple in relation R.
  • Domain constraint: If the value given to an attribute lies outside the domain of that attribute.
  • Referential Integrity constraint: If the value of the foreign key in t refers to a tuple that doesn't show in the referenced relation.

 • Entity Integrity constraint: If the primary key attribute value of new tuple t is given as null.


Related Discussions:- Update operations in dbms - insert operation

List the set operations of sql, List the set operations of SQL? 1) Unio...

List the set operations of SQL? 1) Union 2) Intersect operation 3) The except operation

Define the boyce-codd normal form, Define the Boyce-Codd Normal Form with i...

Define the Boyce-Codd Normal Form with instance and also Compare BCNF and 3NF.  Ans: BCNF: For each functional dependency X->Y in a set F of functional dependencies over relati

What are uncommitted modifications, What are uncommitted modifications? ...

What are uncommitted modifications? The immediate-modification technique permits database modifications to be output to the database whereas the transaction is still in the act

Define the normalisation form, Define in which normalisation form if an att...

Define in which normalisation form if an attribute of a composite key is dependent on an attribute of other composite key. Ans: 3NF A relation is in 3 NF if an attribute of

Dealing with constraints violation, If the deletion violates referential in...

If the deletion violates referential integrity constraint, then three alternatives are available: Default option: - refuse the deletion. It is the job of the DBMS to describ

What is the difference between where and having clauses, What is the differ...

What is the difference between WHERE and HAVING clauses?. Predicates in the WHERE clause applies to every tuple while the predicate in the HAVING clause applies to groups.

What is cardinality ratio, What is Cardinality Ratio? Cardinality Rati...

What is Cardinality Ratio? Cardinality Ratios - The cardinality ratios for relationship kinds specifies the maximum number of relationship instances in which an entity can pa

The result of the union operation between r1 and r2, The result of the UNIO...

The result of the UNION operation between R1 and R2 is a relation that includes? The result of the operation between R1 and R2 includes all the tuples of R1 and R2 which have c

What are the parts of sql language, What are the parts of SQL language? ...

What are the parts of SQL language? The SQL language has various parts: data - definitition language  Data manipulation language  View definition  Transaction contr

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd