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To: Mark Lillywhite <mark@plasticsoftware.com.au>
cc: pgsql-interfaces@postgreSQL.org
Subject: Re: [INTERFACES] JDBC: BigDecimal and Money confusion 
In-reply-to: Your message of Sun, 19 Sep 1999 21:38:03 +1000
	<37E4CB1B.DE31D6B7@plasticsoftware.com.au>
Date: Sun, 19 Sep 1999 11:31:24 -0400
Message-ID: <27326.937755084@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>

Mark Lillywhite <mark@plasticsoftware.com.au> writes:
> Can someone tell me how DECIMAL/NUMERICs are stored? Is there
> somewhere I should look to find out? The end-user docs are a bit
> vague.

Use the source, Luke ;-)

src/include/utils/numeric.h and src/backend/utils/adt/numeric.c
are probably the files to look in.

IIRC from comments that Jan made, it's a pretty brain-dead
representation right now; one decimal digit per byte or something
like that.  He was going to improve it to a base-10000-digit-per-short
format for speed reasons.  Also, I think that there's currently a
difference between the on-disk format and the calculational in-memory
format, which would be nice to get rid of.  We haven't heard from Jan
in a while, so I dunno when or if he's going to get around to that;
if you'd like to tackle it instead, go for it...

			regards, tom lane