Re: Scientific notation for SCN
From: Álvaro G. Vicario <alvaro.NOSPAMTHANX_at_demogracia.com.invalid>
Date: Tue, 29 Sep 2009 17:41:12 +0200
Message-ID: <h9t9qp$503$1_at_news.eternal-september.org>
Ganesh escribió:
> **********
> SQL> select MAX(NEXT_CHANGE#) from V$ARCHIVED_LOG;
>
> MAX(NEXT_CHANGE#)
> -----------------
> 1.3278E+10
>
> SQL> select TO_CHAR(MAX(NEXT_CHANGE#)) from V$ARCHIVED_LOG;
>
> TO_CHAR(MAX(NEXT_CHANGE#))
> ----------------------------------------
> 13278230177
>
> SQL> select TO_CHAR(MAX(NEXT_CHANGE#), 999999999999999999999) from V
> $ARCHIVED_LOG;
>
> TO_CHAR(MAX(NEXT_CHANGE#))
> ----------------------------------------
> 13278230177
>
> **********
>
> But when I give input 1.3278E+10 to my calculator it returns me the
> value as 13278000000. So I am not sure why "TO_CHAR" returned
> 13278230177. So what oracle is doing extra that we are not getting
> here.
Date: Tue, 29 Sep 2009 17:41:12 +0200
Message-ID: <h9t9qp$503$1_at_news.eternal-september.org>
Ganesh escribió:
> **********
> SQL> select MAX(NEXT_CHANGE#) from V$ARCHIVED_LOG;
>
> MAX(NEXT_CHANGE#)
> -----------------
> 1.3278E+10
>
> SQL> select TO_CHAR(MAX(NEXT_CHANGE#)) from V$ARCHIVED_LOG;
>
> TO_CHAR(MAX(NEXT_CHANGE#))
> ----------------------------------------
> 13278230177
>
> SQL> select TO_CHAR(MAX(NEXT_CHANGE#), 999999999999999999999) from V
> $ARCHIVED_LOG;
>
> TO_CHAR(MAX(NEXT_CHANGE#))
> ----------------------------------------
> 13278230177
>
> **********
>
> But when I give input 1.3278E+10 to my calculator it returns me the
> value as 13278000000. So I am not sure why "TO_CHAR" returned
> 13278230177. So what oracle is doing extra that we are not getting
> here.
The 1.3278E+10 you see is the representation of a long number chosen by your SQL console. When you use TO_CHAR() you generate a string so you no longer have a number.
TO_CHAR() accepts an optional argument ("fmt") to specify the format. Docs say:
"If you omit fmt, then n is converted to a VARCHAR2 value exactly long enough to hold its significant digits."
Your SQL console rounds the number to five significant digits but prints the string as-is.
-- -- http://alvaro.es - Álvaro G. Vicario - Burgos, Spain -- Mi sitio sobre programación web: http://borrame.com -- Mi web de humor satinado: http://www.demogracia.com --Received on Tue Sep 29 2009 - 10:41:12 CDT