Re: probable faq: internal format of numerics

Tom Lane wrote:

>Brian Hurt <bhurt(at)janestcapital(dot)com> writes:
>
>
>>This is probably a FAQ, but I've googled the question and haven't found
>>an answer. What is the internal format of numerics?
>>
>>
>
>"Use the source, Luke"
>
>
>

This is what I was hoping to not do. It's generally not possible to
understand a peice of a project out of context- even well commented and
well structured code like the Postgres code looks to be.

That said, it looks like they're doing a variant of my #2- they're
holding 5 decimal digits every 2 bytes, plus an extra byte or so for the
sign. But consider the NumericVar structure defined in numeric.c- is
one of those stored with every row of a table, or are most of the values
stored once per table and only the digits stored in the row? From a
cursory reading of the code, it's hard for me to tell.

Brian