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Focus Keyword: Function and Procedure in PL/SQL

One of the key distinctions between a function and a procedure in PL/SQL is their return type. A function always returns a single value, while a procedure may or may not return any value at all. Additionally, a function can be called in SQL statements like SELECT, while a procedure cannot be directly called in such a way.

Another important difference is that a function must return a value using the RETURN statement, whereas a procedure may or may not have OUT or IN OUT parameters to return values. Functions are generally used for calculations and returning single values, while procedures are used for implementing business logic and performing actions without necessarily returning a value.

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