Home > Pl Sql > Pl Sql Error Handler

Pl Sql Error Handler


Some common internal exceptions have predefined names, such as ZERO_DIVIDE and STORAGE_ERROR. With this technique, you should use a FOR or WHILE loop to limit the number of attempts. For example, in Example 11-23, after the SELECT INTO statement raises ZERO_DIVIDE and the exception handler handles it, execution cannot continue from the INSERT statement that follows the SELECT INTO statement. If the statement fails, Oracle rolls back to the savepoint.

PL/SQL procedure successfully completed. The optional OTHERS handler catches all exceptions that the block does not name specifically. These statements complete execution of the block or subprogram; control does not return to where the exception was raised. If there is no handler for a user-defined exception, the invoking application gets ORA-06510.

Pl Sql Exception Handling Examples

Because a block can reference only local or global exceptions, enclosing blocks cannot reference exceptions declared in a sub-block. In the sub-block, after the COMMIT statement that ends the transaction, put an EXIT statement. I came to my 'version' from the following by no means exhaustive tests: CASE 1: I created a table a with one column, a1 number, and at the sqlplus prompt inserted You can pass an error number to SQLERRM, in which case SQLERRM returns the message associated with that error number.

INVALID_NUMBER ORA-01722 -1722 Conversion of character string to number failed. Typically, you invoke this procedure to raise a user-defined exception and return its error code and error message to the invoker. dbms_output.put_line(TO_CHAR(v_TimeStamp, 'DD-MON-YY HH24:MI:SS')); dbms_output.put(' Module: ' || p_Module); dbms_output.put(' Error #' || p_SeqNum || ': '); dbms_output.put_line(v_ErrorMsg); -- Output the call stack. Pl/sql Raises An Exception In Which Two Of The Following Cases STORAGE_ERROR 06500 -6500It is raised when PL/SQL ran out of memory or memory was corrupted.

The number that SQLCODE returns is negative unless the Oracle error is no data found, in which case SQLCODE returns +100. Pl Sql Exception Handling Best Practices The number that SQLCODE returns is negative unless the Oracle error is no data found, in which case SQLCODE returns +100. But remember, an exception is an error condition, not a data item. More hints The technique is: Encase the transaction in a sub-block.

INVALID_NUMBER ORA-01722 It isn't a number, even though you are treating it like one to trying to turn it into one. User Defined Exception In Pl Sql All rights reserved. The settings for the PLSQL_WARNINGS parameter are stored along with each compiled subprogram. Alternatively, you can use the pragma EXCEPTION_INIT to associate exception names with Oracle error codes.

Pl Sql Exception Handling Best Practices

However, when an exception is raised inside a cursor FOR loop, the cursor is closed implicitly before the handler is invoked. i thought about this In any of the preceding ALTER statements, you set the value of PLSQL_WARNINGS with this syntax: PLSQL_WARNINGS = 'value_clause' [, 'value_clause' ] ... Pl Sql Exception Handling Examples In the exception-handling part, you can include exception handlers for both specific and unknown errors. Functions For Error Trapping Are Contained In Which Section Of A Pl/sql Block You need not worry about checking for an error at every point it might occur.

SUBSCRIPT_OUTSIDE_LIMIT Your program references a nested table or varray element using an index number (-1 for example) that is outside the legal range. The inner block does not have an exception handler for C, so exception C propagates to the outer block. If the optional third parameter is TRUE, the error is placed on the stack of previous errors. Before starting the transaction, mark a savepoint. Pl Sql Continue After Exception

ACCESS_INTO_NULL Your program attempts to assign values to the attributes of an uninitialized (atomically null) object. The pragma must appear somewhere after the exception declaration in the same declarative section, as shown in the following example: DECLARE deadlock_detected EXCEPTION; PRAGMA EXCEPTION_INIT(deadlock_detected, -60); BEGIN null; -- Some operation They are predefined by TimesTen. No matter how severe the error is, you want to leave the database in a consistent state and avoid storing any bad data.

For example, PL/SQL raises the predefined exception NO_DATA_FOUND if a SELECT INTO statement returns no rows. Exception Handling In Oracle Interview Questions THEN -- handle the error WHEN ... By using the WHEN OTHERS exception handler, or 2.

Catching Unhandled Exceptions Remember, if it cannot find a handler for a raised exception, PL/SQL returns an unhandled exception error to the host environment, which determines the outcome.

If there is no enclosing block, control returns to the host environment. BEGIN * ERROR at line 1: ORA-01476: divisor is equal to zero ORA-06512: at "HR.DESCENDING_RECIPROCALS", line 19 ORA-06510: PL/SQL: unhandled user-defined exception ORA-06512: at line 2 Example 11-21 is like Example The RAISE statement is used to explicitly raise an exception and display an error message, returned by the SQLERRM built-in function, and an error code, returned by the SQLCODE built-in function. How Can We Handle Errors In Pl Sql In the latter case, PL/SQL returns an unhandled exception error to the host environment.

Also see "Unsupported predefined errors". User-defined exceptions must be raised explicitly by RAISE statements or invocations of the procedure DBMS_STANDARD.RAISE_APPLICATION_ERROR. This stops normal execution of the block and transfers control to the exception handlers. If you need to know which statement failed, you can use a locator variable: DECLARE stmt INTEGER; name VARCHAR2(100); BEGIN stmt := 1; -- designates 1st SELECT statement SELECT table_name INTO

SELF_IS_NULL Your program attempts to call a MEMBER method on a null instance. Maximum salary is 10000. From there on, the exception propagates normally. When you see an error stack, or sequence of error messages, the one on top is the one that you can trap and handle.

For a workaround, see Defining Your Own Error Messages (RAISE_APPLICATION_ERROR Procedure). Example 11-21 Exception Raised in Exception Handler is Handled by Enclosing Block CREATE PROCEDURE descending_reciprocals (n INTEGER) AUTHID DEFINER IS i INTEGER; i_is_one EXCEPTION; BEGIN BEGIN i := n; LOOP IF The maximum length of an Oracle error message is 512 characters including the error code, nested messages, and message inserts such as table and column names. select * from mytable; < 1 > < 2 > 2 rows found.

To work with PL/SQL warning messages, you use the PLSQL_WARNINGS initialization parameter, the DBMS_WARNING package, and the USER/DBA/ALL_PLSQL_OBJECT_SETTINGS views. You can, however, declare the same exception in two different blocks. For example, perhaps a table you query will have columns added or deleted, or their types changed. Unlike variables, exceptions cannot appear in assignment statements or SQL statements.

PL/SQL declares predefined exceptions globally in package STANDARD, which defines the PL/SQL environment. However, if the statement raises an unhandled exception, the host environment determines what is rolled back. A cursor FOR loop automatically opens the cursor to which it refers, so your program cannot open that cursor inside the loop. If the company has zero earnings, the predefined exception ZERO_DIVIDE is raised.

You can place RAISE statements for a given exception anywhere within the scope of that exception.