Updating sql view

They're great in certain circumstances but they represent a trade-off, and they come with considerable 'small print'. SQL Server views are helpful in many ways, for example in encapsulating complex multi-table query logic, allowing us to simplify client code.

Views make queries faster to write, but they don’t improve the underlying query performance.

A view can contain all rows of a table or select rows from a table.

For example, if one or more of the base tables is subject to frequent updates, then, depending on the aggregations we perform in the indexed view, it is possible that we will increase lock contention on the view’s index.

This article will start from the basics of creating indexed views, and the underlying requirements in order to do so, and then discuss their advantages and the situations in which they can offer a significant boost to query performance.

Not only is this a good practice, it’s also a requirement when creating an indexed view (we’ll discuss further requirements as we progress).

Let’s assume that many applications need to run queries like this, joining the same tables, and referencing the same columns in various combinations.

Views, which are a type of virtual tables allow users to do the following − Database views are created using the CREATE VIEW statement.

Views can be created from a single table, multiple tables or another view. If you omit the WHERE clause, all records in the table will be updated! The WHERE clause specifies which record(s) that should be updated.To create a view, a user must have the appropriate system privilege according to the specific implementation.The basic CREATE VIEW syntax is as follows − ---- ---------- ----- ----------- ---------- | ID | NAME | AGE | ADDRESS | SALARY | ---- ---------- ----- ----------- ---------- | 1 | Ramesh | 32 | Ahmedabad | 2000.00 | | 2 | Khilan | 25 | Delhi | 1500.00 | | 3 | kaushik | 23 | Kota | 2000.00 | | 4 | Chaitali | 25 | Mumbai | 6500.00 | | 5 | Hardik | 27 | Bhopal | 8500.00 | | 6 | Komal | 22 | MP | 4500.00 | | 7 | Muffy | 24 | Indore | 10000.00 | ---- ---------- ----- ----------- ---------- The WITH CHECK OPTION is a CREATE VIEW statement option.A view is nothing more than a SQL statement that is stored in the database with an associated name.

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