Advantages of exceptions, PL-SQL Programming

Assignment Help:

Advantages of Exceptions

Using the exceptions for the error handling has many benefits. Without an exception handling, every time you issue a command, you should ensure for the execution errors:

BEGIN

SELECT ...

-- check for 'no data found' error

SELECT ...

-- check for 'no data found' error

SELECT ...

-- check for 'no data found' error

The Error processing is not clearly separated from general processing; nor is it robust. If you ignore to code a check, the error goes unobserved and is possible to cause other, apparently unrelated errors. With the exceptions, you can handle errors correctly without the requirement to code the multiple checks, which is as shown:

BEGIN

SELECT ...

SELECT ...

SELECT ...

...

EXCEPTION

WHEN NO_DATA_FOUND THEN -- catches all 'no data found' errors

The Exceptions improve readability by letting you isolate the error-handling routines. The primary algorithm is not covered by error recovery algorithms. The Exceptions also improve reliability. You do not need to worry about checking for an error at every point it might occur. An exception handler is just adding to your PL/SQL block. If the exception is still raised in that block or any sub-block, you can be definite it will be handled.


Related Discussions:- Advantages of exceptions

Implement a new discount for return shoppers, Brewbean's is implementing a ...

Brewbean's is implementing a new discount for return shoppers - every fifth completed order receives a 10% discount. The count of orders for a shopper is placed in a packaged varia

Table literals - sql, Table Literals - SQL One might expect SQL to sup...

Table Literals - SQL One might expect SQL to support table literals in the manner illustrated in Example 2.2, but in fact that is not a legal SQL expression. Example: Not a

Assignment of variable - updating a variable, Assignment of Variable - Upda...

Assignment of Variable - Updating a Variable Syntax: SET SN = SID ('S2'); This can obviously be read as "set the variable SN to be equal in value to SID ( 'S2' )".

Declaring records, Declaring Records Whenever you define a RECORD type...

Declaring Records Whenever you define a RECORD type, you may declare records of that type, as the illustration shows: DECLARE TYPE StockItem IS RECORD ( item_no INTEG

Deriving predicates from predicates in sql, Deriving Predicates from Predic...

Deriving Predicates from Predicates in SQL The corresponding section in the theory book describes how predicates can be derived from predicates using (a) the logical connectiv

Pl/sql conditional control: if statements, Pl/sql Conditional Control: IF s...

Pl/sql Conditional Control: IF statements Frequently, it is necessary to take the alternative actions depending on the circumstances. The IF statement execute a series of statem

Currval and nextval - sql pseudocolumns, CURRVAL and NEXTVAL The serie...

CURRVAL and NEXTVAL The series is a schema object which generates the sequential numbers. Whenever you form a sequence, you can specify its primary value and an increment. T

Lob types in pl/sql, LOB Types The large object (LOB) datatypes like BF...

LOB Types The large object (LOB) datatypes like BFILE, BLOB, CLOB, and NCLOB store the blocks of unstructured data (like graphic images, text, video clips, and sound waveforms)

Avoid the not null constraint - performance of application, Avoid the NOT N...

Avoid the NOT NULL Constraint In the PL/SQL, using the NOT NULL constraint incur a performance cost. Consider the illustration as shown below: PROCEDURE calc_m IS m NUMB

Null statement-sequential control, NULL Statement The NULL statement c...

NULL Statement The NULL statement clearly specifies in action; it does nothing other than to pass control to the next statement. It can, though, improve the readability. In a

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