What are the different types of exceptions? | PL SQL

  The three types of exceptions that can be handled at runtime are as follows:
=> Predefined Oracle error — Refers to an undeclared error, which is raised by the Oracle server implicitly
=> Non-predefined Oracle error— Refers to an error declared in the declarative section of the code that is raised by the Oracle server implicitly
=> User-defined error — Refers to an error declared in the declarative section of the code that is raised explicitly