You have a database with multiple tables. You must insert data into the tables by using views.
Which of the following two statements best describes an updatable view?
NOTE: Each correct selection is worth one point.
A . The view must not include the primary key of the table.
B . The view may include GROUP BY or HAVING statements.
C . The view may include a composite field.
D . Each view must reference columns from one table.
E . The view must not include subqueries.
Answer: BD
Explanation:
B: The columns being modified must not be affected by GROUP BY, HAVING, or DISTINCT clauses.
D: Any modifications, including UPDATE, INSERT, and DELETE statements, must reference columns from only one base table.
Incorrect Answers:
A: Primary keys are allowed.
C: The columns cannot be derived in any other way, such as through the following: A computation. The column cannot be computed from an expression that uses other columns.
E: The restrictions apply to any subqueries in the FROM clause of the view, just as they apply to the view itself.
References:
https://docs.microsoft.com/en-us/sql/t-sql/statements/create-view-transact-sql?view=sql-server-2017
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