A view is a subset of a table , virtual table , stored Query. Views are created mainly for security. By creating views we can grant specific rows and columns to user. View doesn’t store any data.
1. Simple View
2. Complex View
Simple View :- If view created based on one table is called Simple View.
Syntax : - Create view < name> [ with <options>]
---- Once view granted to user. You can perform operations on base table through view.
Complex View : A view
1. Based on more than one table.
2. Query Contains
a. Group By Clause
b. Having Clause
c. Aggregate Function
d. Distinct Clause
e. Expression
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