A view is a table that is not physically stored, but instead is derived from the execution of a query. A view is a logical construct created from information contained in one or more tables or previously defined views.
The rows, columns, and data values found in a view are derived from rows, columns, and data values in existing tables or previously defined views.
The following lists some of the benefits of using views:
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Simplifies tables for a specific user. Information not pertinent to a specific user is shielded from the user.
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Limits for security purposes the content of data sets mapped as tables. Restricted information is viewed only by users with rights to the information.
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When used with SELECT statements, specifies a range of acceptable values.
Views are defined through Relational Design Center using the Views node. A view defined for a database processed through Relational Design Center behaves exactly like a view that is defined for any relational database.
The Views input form in Relational Design Center enables you to specify a name for the view, the column names for the view, and the SQL SELECT query that defines the data to be returned when the view is accessed.
SQL views correspond to Enterprise Database Server remaps. Both the view and the remap enable the database administrator to specify alternative views of the physical database files or tables. One significant advantage of the SQL views over Enterprise Database Server remaps is that a remap always performs a linear search if the remap is defined to eliminate records. In contrast, if the view definition eliminates records because the SQL query has a WHERE condition that leaves out some records from the base table, the query optimizer uses indexes where possible, which enhances performance.
