Re: IS and AS
From: O_TEXT <O_TEXT_at_nospam.fr>
Date: Mon, 12 Jan 2009 18:04:03 +0100
Message-ID: <gkft69$11jd$1_at_biggoron.nerim.net>
>> I was wondering what is the difference between IS and AS, in general
>> PL/SQL code.
>>
>>
>> For instance of FUNCTION book_t, how can oracle know if keyword ending
>> the header is IS or AS;
>> I mean if header returns SELF and declare result variable before BEGIN,
>> or if header returns SELF AS RESULT and declare nothing before BEGIN.
>>
>>
>> CREATE OR REPLACE TYPE BODY book_t
>> AS
>> CONSTRUCTOR FUNCTION book_t (id IN INTEGER,
>> title IN VARCHAR2,
>> isbn IN VARCHAR2,
>> pages IN INTEGER)
>> RETURN SELF AS RESULT
>> IS
>> BEGIN
>> SELF.id := id;
>> SELF.title := title;
>> SELF.isbn := isbn;
>> SELF.pages := pages;
>> IF isbn IS NULL OR SELF.ck_digit_okay
>> THEN
>> RETURN;
>> ELSE
>> RAISE_APPLICATION_ERROR(-20000, 'ISBN ' || isbn
>> || ' has bad check digit');
>> END IF;
>> END;
>> ...
Date: Mon, 12 Jan 2009 18:04:03 +0100
Message-ID: <gkft69$11jd$1_at_biggoron.nerim.net>
Shakespeare a écrit :
> O_TEXT schreef:
>> I was wondering what is the difference between IS and AS, in general
>> PL/SQL code.
>>
>>
>> For instance of FUNCTION book_t, how can oracle know if keyword ending
>> the header is IS or AS;
>> I mean if header returns SELF and declare result variable before BEGIN,
>> or if header returns SELF AS RESULT and declare nothing before BEGIN.
>>
>>
>> CREATE OR REPLACE TYPE BODY book_t
>> AS
>> CONSTRUCTOR FUNCTION book_t (id IN INTEGER,
>> title IN VARCHAR2,
>> isbn IN VARCHAR2,
>> pages IN INTEGER)
>> RETURN SELF AS RESULT
>> IS
>> BEGIN
>> SELF.id := id;
>> SELF.title := title;
>> SELF.isbn := isbn;
>> SELF.pages := pages;
>> IF isbn IS NULL OR SELF.ck_digit_okay
>> THEN
>> RETURN;
>> ELSE
>> RAISE_APPLICATION_ERROR(-20000, 'ISBN ' || isbn
>> || ' has bad check digit');
>> END IF;
>> END;
>> ...
> > It's all a matter of parsing.... > > Shakespeare > > BTW: in many cases, AS and IS are interchangeable.
Is it possible to know on which rule PLSQL is based for parsing? Received on Mon Jan 12 2009 - 18:04:03 CET