Oracle PL/SQL is Oracles extension for SQL and Oracle relational database. Oracle PL/SQL adds support for procedural language features such as control statements, loops and classes. This allows the developer to further optimize and refine queries at the database, rather than application layer.
The purpose of a function is generally to compute and return a single value. As a crucial building block of modern programming, being able to define and modify functions is crucial for developers of any skill level.
Knowing the most important features of a programming language is necessary for the effective use of many parts of the framework as well as keeping the code readable.
Public questions (free account) are common interview questions. They are great for practicing, or if you want to filter candidates using the classic problems.
This is a part of latest question addition to our question library.
Consider the following code:
CREATE OR REPLACE FUNCTION count_users RETURN NUMBER IS user_count NUMBER; BEGIN SELECT COUNT(*) INTO user_count FROM users; RETURN user_count; END; /
Select all the statements that are correct.
When the users table is dropped, the count_users function is invalidated.
When the users table is dropped any function, procedure, or package using count_users is invalidated.
When the users table is dropped, any function, procedure, and package using count_users, inside dynamic SQL is invalidated.
When the users table is dropped, the count_users function is also dropped.
As the count_users function is dependent on the users table, any statement dropping the users table will fail.