PL/SQL User's Guide and Reference

RAISE Statement

Description

The RAISE statement stops normal execution of a PL/SQL block or subprogram and transfers control to the appropriate exception handler. For more information, see "User-Defined Exceptions"

Normally, predefined exceptions are raised implicitly by the runtime system. However, RAISE statements can also raise predefined exceptions. User-defined exceptions must be raised explicitly by RAISE statements.

Syntax

raise_statement ::=

RAISE [exception_name];

Keyword and Parameter Description

exception_name

This identifies a predefined or user-defined exception. For a list of the predefined exceptions, see "Predefined Exceptions"

Usage Notes

PL/SQL blocks and subprograms should RAISE an exception only when an error makes it impractical or impossible to continue processing. You can code a RAISE statement for a given exception anywhere within the scope of that exception.

When an exception is raised, if PL/SQL cannot find a handler for it in the current block, the exception propagates. That is, the exception reproduces itself in successive enclosing blocks until a handler is found or there are no more blocks to search. In the latter case, PL/SQL returns an unhandled exception error to the host environment.

Omitting the exception name in a RAISE statement, which is allowed only in an exception handler, reraises the current exception. When a parameterless RAISE statement executes in an exception handler, the first block searched is the enclosing block, not the current block.

Example

In the following example, you raise an exception when an inventoried part is out of stock:

IF quantity_on_hand = 0 THEN
   RAISE out_of_stock;
END IF;