A view is a table that is exported from one or more base tables, and is a "private table" of users that are extracted from an existing base table and composed of several subsets. base table: The definition of a base table refers to the establishment of a basic relational schema, whereas a change refers to the deletion and modification of a basic table that already exists in the database.
Difference: 1, the view is a compiled SQL statement. And the table is not
2. The view has no actual physical record. and the table has.
3, the table is the content, the view is the window
4, the table only uses the physical space and the view does not occupy the physical space,
The view is only the existence of logical concept, the table can be modified in time four
But the view can only have statements created to modify
5, the table is the internal mode, trying to be outside the mode
6, view is a way to view the data table,
You can query the data for some fields in the data table,
Just a collection of some SQL statements. From a security standpoint,
The view does not know the table structure without giving the user access to the data table.
7, the table belongs to the global schema of the table, is a real table, the view belongs to the local mode of the table,
is a virtual table.
8, the creation and deletion of views only affect the view itself, does not affect the corresponding base table.
Contact: A view is a table built on top of a base table, its structure (
The defined column) and the content (that is, all data rows) are from the base table,
It exists based on the existence of a basic table. A view can correspond to a basic table,
You can also correspond to more than one base table.
A view is an abstraction of a basic table and a new relationship in a logical sense
The connections and differences between views and base tables in Oracle.
