How To Raise Error In Oracle 10g
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to your PL/SQL program. With many programming languages, unless you disable error checking, a run-time error such as stack overflow or division by oracle raise exception with message zero stops normal processing and returns control to the operating system. With raise application error in oracle PL/SQL, a mechanism called exception handling lets you bulletproof your program so that it can continue operating in oracle sqlerrm the presence of errors. This chapter contains these topics: Overview of PL/SQL Runtime Error Handling Advantages of PL/SQL Exceptions Summary of Predefined PL/SQL Exceptions Defining Your Own PL/SQL Exceptions oracle exception handling How PL/SQL Exceptions Are Raised How PL/SQL Exceptions Propagate Reraising a PL/SQL Exception Handling Raised PL/SQL Exceptions Overview of PL/SQL Compile-Time Warnings Overview of PL/SQL Runtime Error Handling In PL/SQL, an error condition is called an exception. Exceptions can be internally defined (by the runtime system) or user defined. Examples of internally defined exceptions include division by zero
Oracle Exception When Others
and out of memory. Some common internal exceptions have predefined names, such as ZERO_DIVIDE and STORAGE_ERROR. The other internal exceptions can be given names. You can define exceptions of your own in the declarative part of any PL/SQL block, subprogram, or package. For example, you might define an exception named insufficient_funds to flag overdrawn bank accounts. Unlike internal exceptions, user-defined exceptions must be given names. When an error occurs, an exception is raised. That is, normal execution stops and control transfers to the exception-handling part of your PL/SQL block or subprogram. Internal exceptions are raised implicitly (automatically) by the run-time system. User-defined exceptions must be raised explicitly by RAISE statements, which can also raise predefined exceptions. To handle raised exceptions, you write separate routines called exception handlers. After an exception handler runs, the current block stops executing and the enclosing block resumes with the next statement. If there is no enclosing block, control returns to the host environment. For information on managing errors when using BULK COLLECT, see "Handling FORALL Exceptions with the %B
user-defined exceptions whose names you decide. For more information, see "Defining Your Own PL/SQL
Exception Handling In Oracle 11g
Exceptions". Syntax raise statement ::= Description of the illustration raise_statement.gif oracle predefined exceptions Keyword and Parameter Description exception_name A predefined or user-defined exception. For a list of types of exceptions in oracle the predefined exceptions, see "Summary of Predefined PL/SQL Exceptions". Usage Notes PL/SQL blocks and subprograms should RAISE an exception only when an error https://docs.oracle.com/cd/B19306_01/appdev.102/b14261/errors.htm makes it impractical 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 to successive enclosing blocks, until http://docs.oracle.com/cd/B19306_01/appdev.102/b14261/raise_statement.htm a handler is found or there are no more blocks to search. If no handler is found, PL/SQL returns an unhandled exception error to the host environment. In an exception handler, you can omit the exception name in a RAISE statement, which raises the current exception again. This technique allows you to take some initial corrective action (perhaps just logging the problem), then pass control to another handler that does more extensive correction. When an exception is reraised, the first block searched is the enclosing block, not the current block. Examples For examples, see the following: Example 1-12, "Creating a Stored Subprogram" Example 9-3, "Creating the emp_admin Package" Example 10-3, "Scope of PL/SQL Exceptions" Example 10-9, "Reraising a PL/SQL Exception" Related Topics "Exception Definition" Scripting on this page enhances content navigation, but does not change the content in any way.
TECHNOLOGY: PL/SQL Tracing Lines By Steven Feuerstein Find and report your errors—by line number—in Oracle Database 10g. PL/SQL offers a powerful and flexible exception architecture. Of http://www.oracle.com/technetwork/testcontent/o25plsql-093886.html course, there is always room for improvement, and in Oracle Database 10g, http://plsql-tutorial.com/plsql-exception-handling.htm exception handling takes a big step forward with the introduction of the DBMS_UTILITY.FORMAT_ERROR_BACKTRACE function. This article explores the problem that this function solves and how best to use it. Who Raised That Exception? When an exception is raised, one of the most important pieces of information a in oracle programmer would like to uncover is the line of code that raised the exception. Prior to Oracle Database 10g, one could obtain this information only by allowing the exception to go unhandled. Let's revisit the error-handling behavior available to programmers in Oracle9i Database. Consider this simple chain of program calls in Listing 1: procedure proc3 calls proc2 calls proc1 , error in oracle at which point proc1 raises the NO_DATA_FOUND exception. Notice that there is no error handling in any of the procedures; it is most significantly lacking in the top-level proc3 procedure. If I run proc3 in SQL*Plus, I will see the following results: ERROR at line 1: ORA-01403: no data found ORA-06512: at "SCOTT.PROC1", line 4 ORA-06512: at "SCOTT.PROC2", line 6 ORA-06512: at "SCOTT.PROC3", line 4 ORA-06512: at line 3 Code Listing 1: A stack of procedures CREATE OR REPLACE PROCEDURE proc1 IS BEGIN DBMS_OUTPUT.put_line ('running proc1'); RAISE NO_DATA_FOUND; END; / CREATE OR REPLACE PROCEDURE proc2 IS l_str VARCHAR2(30) := 'calling proc1'; BEGIN DBMS_OUTPUT.put_line (l_str); proc1; END; / CREATE OR REPLACE PROCEDURE proc3 IS BEGIN DBMS_OUTPUT.put_line ('calling proc2'); proc2; END; / This is the error trace dump of an unhandled exception, and it shows that the error was raised on line 4 of proc1. On the one hand, we should be very pleased with this behavior. Now that we have the line number, we can zoom right in on the problem code and fix it. On the other hand,
| PL/SQL Exception Handling Exception Handling In this section we will discuss about the following, 1) What is Exception Handling. 2) Structure of Exception Handling. 3) Types of Exception Handling. 1) What is Exception Handling? PL/SQL provides a feature to handle the Exceptions which occur in a PL/SQL Block known as exception Handling. Using Exception Handling we can test the code and avoid it from exiting abruptly. When an exception occurs a messages which explains its cause is recieved. PL/SQL Exception message consists of three parts. 1) Type of Exception 2) An Error Code 3) A message By Handling the exceptions we can ensure a PL/SQL block does not exit abruptly. 2) Structure of Exception Handling. General Syntax for coding the exception section DECLARE Declaration section BEGIN Exception section EXCEPTION WHEN ex_name1 THEN -Error handling statements WHEN ex_name2 THEN -Error handling statements WHEN Others THEN -Error handling statements END; General PL/SQL statments can be used in the Exception Block. When an exception is raised, Oracle searches for an appropriate exception handler in the exception section. For example in the above example, if the error raised is 'ex_name1 ', then the error is handled according to the statements under it. Since, it is not possible to determine all the possible runtime errors during testing fo the code, the 'WHEN Others' exception is used to manage the exceptions that are not explicitly handled. Only one exception can be raised in a Block and the control does not return to the Execution Section after the error is handled. If there are nested PL/SQL blocks like this. DELCARE Declaration section BEGIN DECLARE Declaration section BEGIN Execution section EXCEPTION Exception section END; EXCEPTION Exception section END; In the above case, if the exception