Explain trigger, Database Management System

Assignment Help:

What is Trigger?

A trigger is a SQL procedure that initiates an action when an event (INSERT, DELETE or UPDATE) occurs. Triggers are kept in and managed by the DBMS. Triggers are used to maintain the referential integrity of data by changing the data in a systematic fashion. A trigger cannot be called or implemented; DBMS automatically fires the trigger as a result of a data modification to the associated table. Triggers can be viewed as same to stored procedures in that both having of procedural logic that is kept at the database level. Stored procedures, though, are not event-drive and are not attached to a specific table as triggers are. Stored procedures are explicitly implemented by invoking a CALL to the procedure whereas triggers are implicitly executed. In addition, triggers can also execute stored procedures.

 


Related Discussions:- Explain trigger

Difference between sql and sql*plus, Difference between SQL and SQL*Plus ...

Difference between SQL and SQL*Plus SQL SQL*Plus SQL is a language SQL *Plus is an environment It   is   bas

Help, #questiononsider the following relation: CAR_SALE =(CAR_ID,oPTION_TYP...

#questiononsider the following relation: CAR_SALE =(CAR_ID,oPTION_TYPE, Option_listpreice, Sale_date, Option_discountedprice)..

ERD, The entity type STUDENT has the following attributes: Student Name, Ad...

The entity type STUDENT has the following attributes: Student Name, Address, Phone, Age, Activity, and No of Years. Activity represents some campus-based student activity, and No o

Which language has recently become the defacto standard, Which language has...

Which language has presently become the defacto standard for interfacing application programs along with relational database system? The language which has recently become the

Lossless-join decomposition, Lossless-Join Decomposition   Let us sh...

Lossless-Join Decomposition   Let us show an intuitive decomposition of a relation. We require a better basis for deciding decompositions since intuition may not always be r

Define atom of domain relational calculus, Define Atom of domain relational...

Define Atom of domain relational calculus An atom has the outline 1 , x 2 , ... , x n > -> r , in which r stands for a relation on n attributes and x 1 , x 2 , ... , x n ar

Define database management system, Normal 0 false false fal...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Give the forms of triggers, Give the forms of triggers? The triggering ...

Give the forms of triggers? The triggering event can be insert or delete. For updated the trigger can state columns. The referencing old row as clause The referencing

The logical dbms architecture, Normal 0 false false false ...

Normal 0 false false false EN-IN X-NONE X-NONE

Non-redundant cover and canonical cover, Given the following set of functio...

Given the following set of functional dependencies {cf?bg, g?d, cdg?f, b?de, d?c} defined on R(b,c,d,e,f,g) a.Find a non-redundant cover. b.Find a canonical cover.

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