What is a view in sql and when can views be updated, Database Management System

Assignment Help:

What is a view in SQL? When can views be updated?

A view is a virtual table which consists of columns from one or more tables. Through it is same to a table; it is stored in the database. It is a query stored as an object. Therefore, a view is an object in that derives its data from one or more tables. These tables are referred to as base or underlying tables.

Views can be updated if they are described on a single table without any aggregate functions could be mapped to an update on the underlying base table under certain conditions.


Related Discussions:- What is a view in sql and when can views be updated

Explain er relationship model, Explain ER Relationship model? An entity...

Explain ER Relationship model? An entity-relationship model (ERM): An entity-relationship model (ERM) is an abstract theoretical illustration of structured data. Entity-relatio

What is data independence, What is data independence? Data Independenc...

What is data independence? Data Independence: Techniques which permit data to be changed without affecting the applications in which procedure it. There are two types of data

Include the create database command, Submit the SQL Statements necessary to...

Submit the SQL Statements necessary to create your database according to the following guidelines: Your SQL statements should exactly mirror your ERD. All primary keys,

What is difference between truncate and delete, What is difference between ...

What is difference between TRUNCATE and DELETE? - Truncate can't be rolled back whereas Delete can be. - Truncate keeps the lock on table whereas Delete keeps the lock on ea

Why are cursors necessary in embedded sql, Why are cursors necessary in emb...

Why are cursors necessary in embedded SQL? A cursor is an object used to store the output of a query for row-by-row processing through the application programs. SQL statements

Distinguish among different kinds of parameters, How can one distinguish am...

How can one distinguish among different kinds of parameters? Input parameters are used to pass data to subroutines. Output parameters are used to pass data from subrout

Entity Relationship for music band managem modeliing, i am required to come...

i am required to come up with entities relationships, optionality and cardinality from a scenario. there is a night club and bookings for a musician band

Write a short note on temporary tables, Write A short note on temporary tab...

Write A short note on temporary tables? Temporary Tables - Temporary tables exists solely for a particular session, or whose data persists for the duration of the transaction

Describe the two alternatives for specifying structural, Describe the two a...

Describe the two alternatives for specifying structural constraints on relationship kinds? Relationship kinds have certain constraints in which limit the possible combination o

Backward recovery (undo), Backward Recovery (UNDO): In this system the unco...

Backward Recovery (UNDO): In this system the uncommitted changes made by a transaction to a database are undone.  Instead the system is reset to the last consistent state of databa

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