But unlike View, the Materialized View are precomputed and stored on a disk like an object, and they are not updated each time they are used. Instead, the materialized view has to be updated manually or with the help of triggers. Materialized View responds faster in comparison to View. It is because the materialized view is precomputed and hence, it does not waste time in resolving the query or joins in the query that creates the Materialized View. Which in turn responses faster to the query made on materialized view.
Where Build clause decides, when to populate the Materialized View. Refresh type decides how to update the Materialized View and trigger decides when to update the materialized View. Materialized View responds faster as compared to View. But View always provides up to date information to the user. Your email address will not be published. On the other hands, Materialized Views are stored on the disc. View can be defined as a virtual table created as a result of the query expression.
However, Materialized View is a physical copy , picture or snapshot of the base table. A view is always updated as the query creating View executes each time the View is used. On the other hands, Materialized View is updated manually or by applying triggers to it.
Materialized View responds faster than View as the Materialized View is precomputed. Materialized View utilizes the memory space as it stored on the disk whereas, the View is just a display hence it do not require memory space. Leave a Reply Cancel reply Your email address will not be published. Since Views are the virtual projection of a query result hence they do not take up any storage area.
This helps in reduction of memory usage and encourages the use of Shared SQL. Whereas the schema created by Materialized Views take up some storage space. This is because it is saved in either the same database as its base table or in a different database. Differences between views and materialized views can also be understood in terms of their usages. Views have a more restrictive behavior towards a base table.
Apart from these differences between views and materialized views, some other important points to keep in mind are:. Log in to leave a comment. Sign in. Log into your account. In order to establish multiple joins in between tables, it is better to utilize index based columns for the purpose of joining tables.
This is because index based columns serve to be faster than the non-index based columns. It may be utilized for isolating applications and prohibiting changes in the definition of database tables.
Views are also used for enhancing security via restricted access to predetermined sets of rows and columns. It is seen that the overall performance of materialized views is better than that of simple, normal views. This is because the data in a materialized view is saved in a table on the hard disk and the table is usually indexed to facilitate faster access and processing.
Additionally, as the joining of tables is carried out at the time of refreshing materialized views, there is no need of firing the join statement as needed in the case of views.
The presence of materialized views are transparent to SQL except in case they are looked up for query rewrites. Query rewrites bring about improvements in the performance of SQL query execution; they are best used in data warehouse environments. It is possible to insert, delete, update and add data with the help of updatable materialized views. Questions related to view vs materialized view remain to be a favourite with interviewers.
Regardless of whether you are a developer, programmer or SQL user, it is important to understand the concept of view and materialized views along with their definitions, usage and differences. In case you have any further inputs with regards to materialized view vs view then we would like to hear from you. Do drop your views in the Comments section below.
Register Login. PPO Diploma vs. Materialized view is mainly used in context to warehousing of data. Storage of data Views are not capable of storing any data, they only point to the data that has to be viewed. A materialized view is capable of storing data. It makes accessibility to data a faster process. DML commands are capable of being made in materialized views. Output A view uses the output of any given query to make it look like a virtual table.
Where used A view is capable of being used in the places wherever a table can be put to use. Impact on base tables All operations carried out on a view are capable of impacting the data present in the base table Views are therefore subjected to the integrity constraints as well as the triggers of base tables. Materialized views can be saved and stored on the hard disk for later use. Materialized views are physical copies of original tables contained by a database.
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