What is a Database View
View is the simply subset of table which are stored logically in a database means a view is a virtual table in the database whose contents are defined by a query. To the database user, the view appears just like a real table, with a set of named columns and rows of data. What is a Database View, A view can join information from several tables together, or we can say that Views are useful for Hiding unwanted information for example adding the ename field to the Order information. Database View is a subset of the database sorted and displayed in a particular way.
They can join and simplify multiple tables into one virtual table. They take up very little storage space because the database contains only the view definition, not the explxin. Furthermore, they can provide results for different calculations like sum and average along with the stored data, acai berry what is it can limit the degree to which tables are exposed to the outer world.
A view is simply a structured query language SQL query stored as an object. If the query is saved as a view, then these overhead activities will only be performed once at the time the view is created. Some relational database engines even allow the data to be updated directly through the view. By: Todd Wasserman Contributor. By: Kishore Jethanandani Contributor. By: Terri Williams Contributor. Dictionary Dictionary Term of the Day. Arithmetic Expression.
Techopedia Terms. Will Bitcoin Survive? How Do Cryptocurrencies Work? Hacking Cryptocurrencies. Will Robots Take Your Job? It Depends. Artificial Intelligence in Cybersecurity. Optimizing Legacy Enterprise Software Modernization. Top 5 Cyber Threats from US Data Protection and Privacy in Considering a VPN?
Make the Right Choice for Your Needs. Follow Connect with us. Sign up. Term of the Day. Best of Techopedia explaih. News and Special Offers occasional. Thank you for subscribing to our newsletter! Connect with us. Techopedia Explains View.
What Does View Mean? Share this Term. Tech moves fast! Stay ahead of the curve with Techopedia! Join nearlysubscribers who receive actionable tech insights from Techopedia.
What Does View Mean?
Sep 17, · Views are used to only display the required data to the users by keeping sensitive data safe. As a database view is associated with many tables upon which the view is created, it simplifies the complexity of the query. The view is used to hide the complexity of the underlying tables used in a database from the end-users. Sep 19, · A view is a subset of a database that is generated from a query and stored as a permanent object. Although the definition of a view is permanent, the data contained therein is dynamic depending on the point in time at which the view is accessed. Views represent a subset of the data contained in a table. They can join and simplify multiple tables. Advantages of MySQL Views. MySQL views bring the following advantages. 1) Simplify complex query. Views help simplify complex queries. If you have any frequently used complex query, you can create a view based on it so that you can reference to the view by using a simple SELECT statement instead of typing the query all over again.
By Priya Pedamkar. Views in SQL are defined as those result sets that work as a stored query on data, and acts as a pre-established query command which is stored by the SQL server in the database dictionary.
A view representing a subset of the data present in a table, and performing functions such as joining and simplification of multiple tables into a single table, data aggregation, handling data complexity, providing security etc. Though a view can be updated, we need to keep a few conditions in the notice. Also, the FROM clause should not contain multiple tables. Despite the many advantages that the views offer, it still has some disadvantages stated as below:.
Views are widely used for their many advantages. They add an extra security layer to the database which is very essential for any relational database management system. Views are flexible in case of exposure of the data to the end-users by showing only the data necessary for example using read-only views to limit the privileges to the users. But also views can be disadvantageous if the underlying table structures change much frequently thereby increasing the complexity of changing the views according to the table structures.
So with many advantages in the picture, views come with a bit less recommended when the performance of the query of data is vital to the business.
It depends upon us to choose the usage of view in our database by validating the business requirement properly so as to gain more advantages from views in order to increase the performance of the system.