Can we update a view ?

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A View created by a single table, can be updated and the updates made on a view will be reflected on the the base table.

An updatable view lets you insert, update, and delete rows in the view and propagate the changes to the target master table.

In order to be updatable, a view cannot contain any of the following constructs:
SET or DISTINCT operators, an aggregate or analytic function, a GROUP BY, ORDER BY, CONNECT BY, or START WITH clause, a subquery (or collection expression) in a SELECT list
or finally (with some exceptions) a JOIN .

Views that are not updatable can be modified using an INSTEAD OF trigger.

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