Pl Sql Error Handling Sql Code
Churchill Run-time errors arise from design faults, coding mistakes, hardware failures, and many other sources. Although you cannot anticipate all possible errors, you can plan to handle certain kinds of errors meaningful 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 zero stops normal processing and returns control to the operating system. With PL/SQL, a mechanism called exception handling lets you "bulletproof" your program so that it can continue operating in the presence of errors. This chapter discusses the following topics: Overview of PL/SQL Error Handling Advantages of PL/SQL Exceptions Predefined PL/SQL Exceptions Defining Your Own PL/SQL Exceptions How PL/SQL Exceptions Are Raised How PL/SQL Exceptions Propagate Reraising a PL/SQL Exception Handling Raised PL/SQL Exceptions Tips for Handling PL/SQL Errors Overview of PL/SQL Error Handling In PL/SQL, a warning or error condition is called an exception. Exceptions can be internally defined (by the run-time system) or user defined. Examples of internally defined exceptions include division by zero 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 return
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 zero stops normal processing and returns control to the operating system. With PL/SQL, a mechanism called exception handling lets you bulletproof your program so that it can continue operating in the presence of errors. This chapter contains these topics: Overview of PL/SQL Runtime https://docs.oracle.com/cd/A97630_01/appdev.920/a96624/07_errs.htm Error Handling Advantages of PL/SQL Exceptions Summary of Predefined PL/SQL Exceptions Defining Your Own PL/SQL Exceptions 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 https://docs.oracle.com/cd/B19306_01/appdev.102/b14261/errors.htm an exception. Exceptions can be internally defined (by the runtime system) or user defined. Examples of internally defined exceptions include division by zero 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 hand
Server MySQL MariaDB PostgreSQL SQLite MS Office Excel Access Word Web Development HTML CSS Color Picker https://www.techonthenet.com/oracle/exceptions/sqlcode.php Languages C Language More ASCII Table Linux UNIX Java Clipart Techie Humor Advertisement Oracle Basics Oracle Advanced Oracle Cursors Oracle Exception Handling Named Programmer-Defined http://psoug.org/reference/exception_handling.html Exception Named System Exception WHEN OTHERS Clause SQLCODE SQLERRM Oracle Foreign Keys Oracle Loops/Conditionals Oracle Transactions Oracle Triggers String/Char Functions Numeric/Math Functions Date/Time Functions pl sql Conversion Functions Analytic Functions Advanced Functions NEXT: SQLERRM Oracle / PLSQL: SQLCODE Function This Oracle tutorial explains how to use the Oracle/PLSQL SQLCODE function with syntax and examples. What does the SQLCODE Function do? The SQLCODE function returns the error number associated with the most recently raised error pl sql error exception. This function should only be used within the Exception Handling section of your code: Syntax The syntax for the SQLCODE function in Oracle/PLSQL is: SQLCODE Parameters or Arguments There are no parameters or arguments for the SQLCODE function. Note See also the SQLERRM function. Example Since EXCEPTION HANDLING is usually written with the following syntax: EXCEPTION WHEN exception_name1 THEN [statements] WHEN exception_name2 THEN [statements] WHEN exception_name_n THEN [statements] WHEN OTHERS THEN [statements] END [procedure_name]; You could use the SQLCODE function to raise an error as follows: EXCEPTION WHEN OTHERS THEN raise_application_error(-20001,'An error was encountered - '||SQLCODE||' -ERROR- '||SQLERRM); END; Or you could log the error to a table using the SQLCODE function as follows: EXCEPTION WHEN OTHERS THEN err_code := SQLCODE; err_msg := SUBSTR(SQLERRM, 1, 200); INSERT INTO audit_table (error_number, error_message) VALUES (err_code, err_msg); END; NEXT: SQLERRM Share this page: Advert
Functions PSOUG Forum Oracle Blogs Search the Reference Library pages: FreeOracle MagazineSubscriptionsand Oracle White Papers Oracle Exception Handling Version 11.1 General NOTE: How Oracle Does Implicit Rollbacks Before executing an INSERT, UPDATE, or DELETE statement, Oracle marks an implicit savepoint (unavailable to you). If the statement fails, Oracle rolls back to the savepoint. Normally, just the failed SQL statement is rolled back, not the whole transaction. However, if the statement raises an unhandled exception, the host environment determines what is rolled back. If you exit a stored subprogram with an unhandled exception, PL/SQL does not assign values to OUT parameters. Also, PL/SQL does not roll back database work done by the subprogram. At the level of the SQL*Plus prompt, every update/insert/delete has one implicit savepoint, and also the invocation of any unnamed block. Below that, the unnamed block itself has 'sub' savepoints - one foreach insert/update/delete statement in it, and one for each subprogram unit. And so on down the line. If an error occurs, and that error is handled at any level by the time we're back at the SQL*Plus prompt, we only rollback to the immediate savepoint at the start of the update/insert/delete that errors. Otherwise we rollback to the top-level 'virtual' savepoint currently in existence, which is my offending unnamed block. That is, a handled error is handled and so can be dealt with without rolling back all the way to the top. It is handled and the transaction proceeds. Commits define the end of a transaction (and start of a new one) - rollbacks only define the end of a transaction if they rollback to the last commit, rather than savepoint (whether explicit or implicit). I came to my 'version' from the following by no means exhaustive tests: