How exceptions propagate in pl/sql programming?, PL-SQL Programming

Assignment Help:

How Exceptions Propagate ?

Whenever an exception is raised, and if the PL/SQL cannot find a handler for it in the present subprogram or block, the exception propagates. That is, the exceptions reproduce it in the succeeding enclosing blocks until a handler is found or there are no more blocks to search. In the latter situation, the PL/SQL returns an unhandled exception error to the host atmosphere.

Though, exceptions cannot propagate across the remote procedure calls (RPCs). As a result, the PL/SQL block cannot catch an exception raised by a remote subprogram.

1751_exceptions propogate.png

 

581_exceptions propogate1.png

 

2358_exceptions propogate2.png

An exception can propagate additional than its scope, that is, additional than the block in which it was declared. Consider the illustration which is as shown below:

BEGIN

...

DECLARE ---------- sub-block begins

past_due EXCEPTION;

BEGIN

...

IF ... THEN

RAISE past_due;

END IF;

END; ------------- sub-block ends

EXCEPTION

...

WHEN OTHERS THEN

ROLLBACK;

END;

As the block in which the exception past_due was declared has no handler, the exception propagates to the enclosing block. But, according to the scope rules, the enclosing blocks cannot reference the exceptions declared in a sub-block. Therefore, only an OTHERS handler can catch the exception.


Related Discussions:- How exceptions propagate in pl/sql programming?

Level - sql pseudocolumns, LEVEL You use the LEVEL with the SELECT CON...

LEVEL You use the LEVEL with the SELECT CONNECT BY statement to categorize rows from a database table into a tree structure. The LEVEL returns the level number of a node in a

Difference between implicit and explicit cursor, Implicit Cursor is declare...

Implicit Cursor is declared and used by the oracle environment internally. while the explicit cursor is declared and used by the external user. more over implicitly cursors are no

Pl/sql engine, Architecture The PL/SQL run-time system and compilation ...

Architecture The PL/SQL run-time system and compilation is a technology, not an independent product. Consider this technology as an engine that compiles and executes the PL/SQL

Union and or - sql, UNION and OR - SQL SQL supports UNION explicitly b...

UNION and OR - SQL SQL supports UNION explicitly but differently from the way it supports JOIN explicitly. As we have seen, JOIN is used exclusively within the FROM clause, su

Relational algebra, Define basic operators of relational algebra with an ex...

Define basic operators of relational algebra with an example each

Keyword and parameter description - if statement, Keyword and Parameter Des...

Keyword and Parameter Description: boolean_expression: This is an expression which results the Boolean value TRUE, FALSE, & NULL. It is related with a series of statement

Dbms, DBMS: The answer to this question is of course given in of the t...

DBMS: The answer to this question is of course given in of the theory book. This book is concerned with SQL DBMSs and SQL databases in particular. Soon we will be looking a

Design a script and integrate procedures, Initial thought process: Design...

Initial thought process: Design a script which was simple and user friendly. Integrate procedures/functions to extract data under the hood. I focused on giving the user the opt

Using prior and next - collection method, Using PRIOR and NEXT The PRI...

Using PRIOR and NEXT The PRIOR(n) returns the index number that precede index n in a collection. The NEXT(n) returns the index number which succeed the index n. If n has no pr

Assignment2, How do I display usernames for students from a student table, ...

How do I display usernames for students from a student table, assigning each student a username initials001 (initials is the actual student initials), and if the students initials

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd