Error Handling Framework In Pl Sql
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March 2012 Oracle Magazine Online 2016 2015 2014 2013 2012 2011 2010 January 2012 March 2012 May 2012 July 2012 September 2012 November 2012 As Published In March/April 2012 TECHNOLOGY: pl sql error handling best practices PL/SQL Error Management By Steven Feuerstein Part 6 in a pl sql error handling when others series of articles on understanding and using PL/SQL Even if you write absolutely perfect PL/SQL programs, it is possible pl sql exception handling best practices and even likely that something will go wrong and an error will occur when those programs are run. How your code responds to and deals with that error often spells the difference pl sql exception handling in loop between a successful application and one that creates all sorts of problems for users as well as developers. This article explores the world of error management in PL/SQL: the different types of exceptions you may encounter; when, why, and how exceptions are raised; how to define your own exceptions; how you can handle exceptions when they occur; and how you can report information
Pl Sql Exception Handling Interview Questions
about problems back to your users. Exception Overview There are three categories of exceptions in the world of PL/SQL: internally defined, predefined, and user-defined. An internally defined exception is one that is raised internally by an Oracle Database process; this kind of exception always has an error code but does not have a name unless it is assigned one by PL/SQL or your own code. An example of an internally defined exception is ORA-00060 (deadlock detected while waiting for resource). A predefined exception is an internally defined exception that is assigned a name by PL/SQL. Most predefined exceptions are defined in the STANDARD package (a package provided by Oracle Database that defines many common programming elements of the PL/SQL language) and are among the most commonly encountered exceptions. One example is ORA-00001, which is assigned the name DUP_VAL_ON_INDEX in PL/SQL and is raised when a unique index constraint is violated. A user-defined exception is one you have declared in the declaration section of a program unit. User-defined exceptions can be associated with an internally defined exception (that is, you can give a name to an otherwise unnamed
you should consider them as your closest friends. They are the ones that honestly
T Sql Error Handling
say what is wrong with your program. We cannot foresee all transact sql error handling possible problematic events, and even the best programmers write bugs. Exceptions There are three kinds of pl sql raise exception exceptions Internally defined: A system error, defined by Oracle, that occurs. Predefined: The most common internally defined exceptions that are given predefined names. User defined: A logical http://www.oracle.com/technetwork/issue-archive/2012/12-mar/o22plsql-1518275.html error which you define and raise yourself System errors could occur from improper coding, like the “ORA-01001: Invalid cursor”, which you should try to fix as soon as possible in your code. And the “TOO_MANY_ROWS”-error might give you clues about bad data quality. To resolve these bugs, it is important to know where, http://allthingsoracle.com/error-handling/ when and why it happened. But system errors could also occur from hardware failures, like the “ORA-12541: TNS: no listener”, when an ftp-server might be unreachable over the network. In that case, all you can do, and should do, is provide proper error handling and transaction management, and give as detailed information as possible about this situation to the people that need to know. These system-errors always have an error number assigned, so you can easily identify the error. The 22 predefined exceptions also have a name assigned, which allows for easier, and more readable exception handling. For the other, non-predefined, system-errors, a name can be linked by using the pragma “EXCEPTION_INIT”. DECLARE network_error EXCEPTION; PRAGMA EXCEPTION_INIT(network_error, -12541); BEGIN ... EXCEPTION WHEN too_many_rows THEN ... WHEN network_error THEN ... END; User defined errors we will raise ourselves. They can be given a number and a name. To raise a user defined error with a chosen number and error mes
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About http://stackoverflow.com/questions/32568953/using-a-pl-sql-procedure-to-log-errors-and-handle-exceptions Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join http://plsql-tutorial.com/plsql-exception-handling.htm the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up Using a pl/sql procedure to pl sql log errors and handle exceptions up vote 0 down vote favorite so far stack overflow and the oracle forums and docs have been my best friend in learning PLSQL. I'm running into an issue here. Any advice is appreciated. I'm writing a procedure that would be used to log any errors a package may encounter and log them into the error log table I created. here sql error handling is my code thus far. CREATE OR REPLACE PROCEDURE APMS.test_procedure AS procedure write_error_log (errcode number, errstr varchar2, errline varchar2) is pragma autonomous_transaction; -- this procedure stays in its own new private transaction begin INSERT INTO error_log (ora_err_tmsp, ora_err_number, ora_err_msg, ora_err_line_no) values (CURRENT_TIMESTAMP, errcode, errstr, errline); COMMIT; -- this commit does not interfere with the caller's transaction. end write_error_log; BEGIN INSERT INTO mockdata VALUES ('data1', 'mockname', 'mockcity'); exception when others then write_error_log(sqlcode,sqlerrm,dbms_utility.format_error_backtrace); raise; END test_procedure; / In the procedure I currently am using a mockdata table to induce an invalid number error and log that to the error_log table. At this point the error log table proves to be functional and inserts the data needed. The next step for me is to use this procedure to be used in the exception handlers in other programs so that the error is caught and logged to the table. Currently, my procedure is only unique to the mock_data table. My mentor/superior is telling me I need to pass this program some parameters to use it in other packages and exception handlers. I'm just having a bit of trouble. Any help would be appreciated thank you! oracle stored-procedures plsql err
| 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 is raised in the inner block it should be handled in the exception block of the inner PL/SQL block else the control moves to the Exception block of the next upper PL/SQL Block. If no