Shulou(Shulou.com)06/01 Report--

Choose three

Which three statements are true about views in an Orade batabase?

A) A SELECT statement cannot contain a where clause when querying a view contaning a WHERE clause in its defining query

B) Rows inserted into a table using a view are retained in the table if the view is dopped

C) Views can join tables only if they belong to the same schema.

D) Views have no segment.

E) Views have no object number.

F) A view can be created that refers to a non-existent table in its defining query.

Answer:BD?

(parse:

After the experiment, An is wrong; C is wrong, and the view can be queried with tables of different schemas; F is wrong, if there is no table in the subquery, the view will report an error; the view is also an object, so the answer E is wrong.

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