MADEEASY

Question

Which of the following statement true about views ?
a.Views allowed to update if defined over single relation without aggregation.
b. Views allowed to update if defined over multiple relations without aggregation.
c. Views allowed to update if defined over single relation even with aggregation.
d. Views allowed to update if defined over multiple relations with aggregation.

Comments

With respect to Oracle, options c and d are outright false. If group functions are present, views are not updatable.

Option a is true. Truth of option b depends on certain conditions.

Check this for details.

Answer 1

In SQL views are allowed to update if defined over single relation and without aggregation.

so, option A is correct.

ref : https://dev.mysql.com/doc/refman/5.7/en/views.html