Home > Pl Sql > Pl Sql Cursor Error Handling

Pl Sql Cursor Error Handling


That is, normal execution stops and control transfers to the exception-handling part of your PL/SQL block or subprogram. Example 11-7 Anonymous Block Avoids ZERO_DIVIDE DECLARE stock_price NUMBER := 9.73; net_earnings NUMBER := 0; pe_ratio NUMBER; BEGIN pe_ratio := CASE net_earnings WHEN 0 THEN NULL ELSE stock_price / net_earnings END; It could represent a mistake, or it could be intentionally hidden by a debug flag, so you might or might not want a warning message for it. If no exception has been raised, SQLCODE returns zero and SQLERRM returns the message: ORA-0000: normal, successful completion. click site

WHEN ZERO_DIVIDE THEN -- handles 'division by zero' error dbms_output.put_line('Company must have had zero earnings.'); pe_ratio := null; WHEN OTHERS THEN -- handles all other errors dbms_output.put_line('Some other kind of error DECLARE name VARCHAR2(20); ans1 VARCHAR2(3); ans2 VARCHAR2(3); ans3 VARCHAR2(3); suffix NUMBER := 1; BEGIN FOR i IN 1..10 LOOP -- try 10 times BEGIN -- sub-block begins SAVEPOINT start_transaction; -- mark Redeclared Predefined Exceptions Oracle recommends against redeclaring predefined exceptions—that is, declaring a user-defined exception name that is a predefined exception name. (For a list of predefined exception names, see Table 11-3.) Here’s an example of calling the function: BEGIN DBMS_OUTPUT.put_line ( single_number_value ( 'employees', 'salary', 'employee_id=138')); END; As with SELECT-INTO, EXECUTE IMMEDIATE-INTO will raise NO_DATA_FOUND if no rows are found and TOO_MANY_ROWS https://docs.oracle.com/cd/B13789_01/appdev.101/b10807/07_errs.htm

Oracle Cursor Exception Handling Within A Loop

The average person thinks he's above average! sample code------------------ cur c1 is select * from T1; open c1 loop fetch c1 into cur_id; select name into var_name from t2 where id = cur_id; exception when no_data_found then continue From there on, the exception propagates normally. 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

CASE_NOT_FOUND 06592 -6592 It is raised when none of the choices in the WHEN clauses of a CASE statement is selected, and there is no ELSE clause. Example 11-11 Reraising Exception DECLARE salary_too_high EXCEPTION; current_salary NUMBER := 20000; max_salary NUMBER := 10000; erroneous_salary NUMBER; BEGIN BEGIN IF current_salary > max_salary THEN RAISE salary_too_high; -- raise exception END IF; b) to make the user-defined exception look like an Oracle error. Cursor Exceptions In Oracle In Example 11-11, the handling of the exception starts in the inner block and finishes in the outer block.

You must raise a user-defined exception explicitly. Pl Sql Exception Handling Continue Loop Typically, you invoke this procedure to raise a user-defined exception and return its error code and error message to the invoker. But, according to the scope rules, enclosing blocks cannot reference exceptions declared in a sub-block. http://www.oracle.com/technetwork/issue-archive/2013/13-mar/o23plsql-1906474.html For Example: Lets consider the product table and order_items table from sql joins to explain user-defined exception.

However, the same scope rules apply to variables and exceptions. Pl Sql Exception Handling Best Practices The time now is 01:57. When the i_is_one exception handler raises ZERO_DIVIDE, the exception propagates immediately to the invoker (therefore, the ZERO_DIVIDE exception handler does not handle it). You can avoid unhandled exceptions by coding an OTHERS handler at the topmost level of every PL/SQL program.

Pl Sql Exception Handling Continue Loop

COLLECTION_IS_NULL 06531 -6531 It is raised when a program attempts to apply collection methods other than EXISTS to an uninitialized nested table or varray, or the program attempts to assign values http://stackoverflow.com/questions/8566339/plsql-cursors-handle-exception-and-return-back-to-the-execution-flow TIMEOUT_ON_RESOURCE A time-out occurs while Oracle is waiting for a resource. Oracle Cursor Exception Handling Within A Loop You can use the pragma EXCEPTION_INIT to associate exception names with other Oracle error codes that you can anticipate. Pl Sql Exception Handling Examples Raising Exceptions with the RAISE Statement PL/SQL blocks and subprograms should raise an exception only when an error makes it undesirable or impossible to finish processing.

BEGIN Execution section EXCEPTION WHEN NO_DATA_FOUND THEN dbms_output.put_line ('A SELECT...INTO did not return any row.'); END; b) Unnamed System Exceptions Those system exception for which oracle does not provide a name http://setiweb.org/pl-sql/pl-sql-error-handling.php For example, you might define an exception named insufficient_funds to flag overdrawn bank accounts. If the statement doesn’t identify any rows to be fetched, Oracle Database will raise the NO_DATA_FOUND exception. If a stored subprogram exits with an unhandled exception, PL/SQL does not roll back database changes made by the subprogram. Oracle Raise Exception With Message

The following block redeclares the predefined exception INVALID_NUMBER. But when the handler completes, the block is terminated. The number that SQLCODE returns is negative unless the Oracle error is no data found, in which case SQLCODE returns +100. navigate to this website I tried that and updated in the question.

Otherwise, you can handle them only with OTHERS exception handlers. Exception No Data Found Oracle Without exception handlers, you must check for every possible error, everywhere that it might occur, and then handle it. Note: When using pragma RESTRICT_REFERENCES to assert the purity of a stored function, you cannot specify the constraints WNPS and RNPS if the function calls SQLCODE or SQLERRM.

For a workaround, see "Defining Your Own Error Messages: Procedure RAISE_APPLICATION_ERROR".

SQL aggregate functions such as AVG and SUM always return a value or a null. I need to write a function with the following header: FUNCTION plch_one_employee ( employee_id_in IN PLS_INTEGER) RETURN plch_employees%ROWTYPE that returns a record that contains the row of information for the Make your programs robust enough to work even if the database is not in the state you expect. Exception Part Can Be Defined Twice In Same Block This is especially handy when you need to use PL/SQL, in addition to SQL, to build the result set.

Learn the names and causes of the predefined exceptions. Retrieving the Error Code and Error Message: SQLCODE and SQLERRM In an exception handler, you can use the built-in functions SQLCODE and SQLERRM to find out which error occurred and to When you declare a cursor in a package (that is, not inside a subprogram of the package) and the cursor is opened, it will stay open until you explicitly close it http://setiweb.org/pl-sql/pl-sql-close-cursor-error.php Jobs Send18 Whiteboard Net Meeting Tools Articles Facebook Google+ Twitter Linkedin YouTube Home Tutorials Library Coding Ground Tutor Connect Videos Search PL/SQL Tutorial PL/SQL - Home PL/SQL - Overview PL/SQL -

END; In this example, if the SELECT INTO statement raises a ZERO_DIVIDE exception, the local handler catches it and sets pe_ratio to zero. Raising Internally Defined Exception with RAISE Statement Although the runtime system raises internally defined exceptions implicitly, you can raise them explicitly with the RAISE statement if they have names. Example 11-23 Exception Handler Runs and Execution Ends DROP TABLE employees_temp; CREATE TABLE employees_temp AS SELECT employee_id, salary, commission_pct FROM employees; DECLARE sal_calc NUMBER(8,2); BEGIN INSERT INTO employees_temp (employee_id, salary, commission_pct) This program asks for a customer ID, when the user enters an invalid ID, the exception invalid_id is raised.

Errors can also arise from problems that are independent of your code—for example, disk storage or memory hardware failure—but your code still must take corrective action. Test your code with different combinations of bad input data to see what potential errors arise. Compile-Time Warnings While compiling stored PL/SQL units, the PL/SQL compiler generates warnings for conditions that are not serious enough to cause errors and prevent compilation—for example, using a deprecated PL/SQL feature. The syntax is: PRAGMA EXCEPTION_INIT (exception_name, error_code) For semantic information, see "EXCEPTION_INIT Pragma".

If the transaction succeeds, the COMMIT and EXIT statements execute. To see any warnings generated during compilation, you use the SQL*Plus SHOW ERRORS command or query the USER_ERRORS data dictionary view. You can have any number of exception handlers, and each handler can associate a list of exceptions with a sequence of statements. 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.

RAISE_APPLICATION_ERROR is part of package DBMS_STANDARD, and as with package STANDARD, you do not need to qualify references to it.