Wisdom of Helios


View and Materialized view

View –  View evaluates the data/dataset in the tables underlying the view definition when the view is queried.

The data/dataset of view is not stored anywhere.

View is a logical or virtual memory based.

Materialized view – Materialized View is physical duplication of data of  a Table.  The data inside the table may come from           join quires of other tables.

The Data or Dataset is stored in a table.

Materialized views are disk based.

(Materialized views are schema objects that can be used to summarize precompute replicate and distribute data. E.g. to construct a data warehouse.)

Advantage of using a view

View always returns the latest data. no REFRESH of the view is required.

Drawback of using a view

Since view collects data from join queries of multiple tables and when the view is queried it performs the join operations each time. So its performance depends on how good a select statement the view is based on. If the select statement used by the view joins many tables, or uses joins based on non-indexed columns, the view could perform poorly.

Advantage of using a Materialized view

when you query a materialized view, you are querying a table, which may also be indexed. In addition, because all the joins have been resolved at materialized view refresh time, you pay the price of the join once , rather than each time you select from the materialized view.

An updatable materialized view lets you insert update and delete.

Drawback of using a Materialized view

The data you get back from the materialized view is only as up to date as the last time the materialized view has been REFRESHed.

(Materialized views can be set to refresh manually, on a set schedule, or based on the database detecting a change in data from one of the underlying tables)

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Tools for Web Developers

Open Source CMS








Kentico CMS for ASP.NET


client-side technologies

ASP Ajax

Code Repository :
TFS Online

Technologies  plan to investigate and work with in the near future

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Assemblies in .net

Assemblies are re-usable, self-descriptive, version-able building blocks of  a .net application. It stores all the necessary information of the deployment and versioning about the application.

The metadata of the assembly is called “manifest”.

An Assembly can be formed into a single file or multiple files. In case of  “Single File” the file will be single EXE or DLL file.In “Case of multiple files” , an assembly can consist of a number of executable files and resource files. In that case, the manifest may be a separate file, or it may be included in one of the executable files.

Task of an Assembly File :

Assemblies enable the common language runtime to locate and securely execute code. In particular, the runtime uses assemblies for the following purposes:

  • Establishing security and version identity for code.
  • Providing a scope for class and type resolution.
  • Locating classes to load.

Assembly and Versioning :

One of the primary goals of assemblies is versioning. Specifically, assemblies provide a means for developers to specify version rules between different software components, and to have those rules enforced at run time.

Because assemblies are the building blocks of applications, they are the logical point for specifying and enforcing version information. Each assembly has a specific version number as part of its identity.

The version number is stored in the assembly’s manifest along with other identity information, including the friendly name and supported locales. The fact that a version number is part of an assembly’s identity is the key to versioning: AssemblyA, version 1 and AssemblyA, version 2 are two completely different entities, and are treated as such at run time.