Pl Sql Cursor Error
When there is more than one row in a cursor we can use loops along with explicit cursor attributes to fetch all the records. If no handler is found, PL/SQL returns an unhandled exception error to the host environment. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description) 2 values('02','Alison', 'Mathews', to_date('19760321','YYYYMMDD'), to_date('19860221','YYYYMMDD'), 6661.78, 'Vancouver','Tester') 3 / 1 row created. General Form of using an explicit cursor is: DECLARE variables; records; create a cursor; BEGIN OPEN cursor; FETCH cursor; process the records; CLOSE cursor; END; Explicit Cursor, Lets Look at the this content
With exceptions, you can reliably handle potential errors from many statements with a single exception handler: BEGIN SELECT ... 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 However, when an exception is raised inside a cursor FOR loop, the cursor is closed implicitly before the handler is invoked. RAISE_APPLICATION_ERROR is part of package DBMS_STANDARD, and as with package STANDARD, you do not need to qualify references to it. Check This Out
Pl Sql Exception Handling Examples
Here is a very simple example: CREATE OR REPLACE FUNCTION numbers_from ( query_in IN VARCHAR2) RETURN SYS_REFCURSOR IS l_return SYS_REFCURSOR; BEGIN OPEN l_return FOR query_in; RETURN l_return; END numbers_from; And here Place the sub-block inside a loop that repeats the transaction. In the loop we use fetch statement again (line no 15) to process the next row. If the transaction fails, control transfers to the exception handler, where you roll back to the savepoint undoing any changes, then try to fix the problem.
For example, the predefined exception NO_DATA_FOUND is raised when a SELECT INTO statement returns no rows. For example, you might define an exception named insufficient_funds to flag overdrawn bank accounts. For example, the following declaration raises an exception because the constant credit_limit cannot store numbers larger than 999: DECLARE credit_limit CONSTANT NUMBER(3) := 5000; -- raises an exception BEGIN NULL; EXCEPTION Oracle Cursor For Loop FETCH the data from cursor into PL/SQL variables or records in the Execution Section.
From there on, the exception propagates normally. You can also treat particular messages as errors instead of warnings. select_statement – A select query which returns multiple rows. find more Cursor with a FOR Loop: When using FOR LOOP you need not declare a record or variables to store the cursor values, need not open, fetch and close the cursor.
Associating a PL/SQL Exception with a Number: Pragma EXCEPTION_INIT To handle error conditions (typically ORA- messages) that have no predefined name, you must use the OTHERS handler or the pragma EXCEPTION_INIT. Cursor Exceptions In Oracle Why are planets not crushed by gravity? 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 How PL/SQL Exceptions Are Raised How I added begin and end , there are still more errors in the structure.
Pl Sql Exception Handling Continue Loop
So, PL/SQL predefines some common Oracle errors as exceptions. try this Do these physical parameters seem plausible? Pl Sql Exception Handling Examples ORA-01403 TOO_MANY_ROWS When you SELECT or fetch more than one row into a record or variable. Oracle Cursor Exception Handling Within A Loop Handle named exceptions whenever possible, instead of using WHEN OTHERS in exception handlers.
If you redeclare a global exception in a sub-block, the local declaration prevails. If the transaction succeeds, commit, then exit from the loop. select dbms_warning.get_warning_setting_string() from dual; -- When we recompile the procedure, we will see a warning about the dead code. dbms_output.put_line('Can''t handle an exception in a declaration.'); END; / Handlers in the current block cannot catch the raised exception because an exception raised in a declaration propagates immediately to the enclosing Cursor Example In Oracle
For a workaround, see "Defining Your Own Error Messages: Procedure RAISE_APPLICATION_ERROR". Thus, a block or subprogram can have only one OTHERS handler. These are known as user-defined exceptions. have a peek at these guys If earnings are zero, the function DECODE returns a null.
Pre-defined Exceptions PL/SQL provides many pre-defined exceptions, which are executed when any database rule is violated by a program. Pl Sql Exception Handling Best Practices The following is a procedure that will display the values of any numeric column for all rows specified in the WHERE clause: CREATE OR REPLACE PROCEDURE show_number_values ( table_in IN VARCHAR2, If the parameter is FALSE (the default), the error replaces all previous errors.
WHEN OTHERS THEN -- optional handler sequence_of_statements3 END; To catch raised exceptions, you write exception handlers.
We can also create a record with a cursor by replacing the table name with the cursor name. It is created on a SELECT Statement which returns more than one row. If the exception is ever raised in that block (or any sub-block), you can be sure it will be handled. Ora-01001: Invalid Cursor 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 -
As the following example shows, use of the OTHERS handler guarantees that no exception will go unhandled: EXCEPTION WHEN ... If so, do it by making a call to a procedure declared with the PRAGMA AUTONOMOUS_TRANSACTION, so that you can commit your debugging information, even if you roll back the work Exceptions can be internally defined (by the run-time system) or user defined. check my blog The default exception will be handled using WHEN others THEN: DECLARE
Make your programs robust enough to work even if the database is not in the state you expect. When that bonus pool is exhausted, it stops fetching and commits all changes. Before starting the transaction, mark a savepoint. In this case, I declare a record based on the employees table and fetch all columns (with a SELECT *) into that record for the specified row.
You can place RAISE statements for a given exception anywhere within the scope of that exception. Unlike variables, exceptions cannot appear in assignment statements or SQL statements. END IF; END; / The calling application gets a PL/SQL exception, which it can process using the error-reporting functions SQLCODE and SQLERRM in an OTHERS handler. A pragma is a compiler directive that is processed at compile time, not at run time.
Take the Challenge Each PL/SQL 101 article offers a quiz to test your knowledge of the information provided in it. You can avoid such problems by declaring individual variables with %TYPE qualifiers, and declaring records to hold query results with %ROWTYPE qualifiers. Using Exception Handling we can test the code and avoid it from exiting abruptly. The syntax for declaring an exception is: DECLARE my-exception EXCEPTION; Example: The following example illustrates the concept.