Re: Fixed length data types issue - Mailing list pgsql-hackers

From Martijn van Oosterhout
Subject Re: Fixed length data types issue
Date
Msg-id 20060907110233.GG10093@svana.org
Whole thread Raw
In response to Re: Fixed length data types issue  (Gregory Stark <stark@enterprisedb.com>)
Responses Re: Fixed length data types issue  (Gregory Stark <stark@enterprisedb.com>)
Re: Fixed length data types issue  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
On Thu, Sep 07, 2006 at 11:57:26AM +0100, Gregory Stark wrote:
> Just brain storming here. But what happens if we make Datum 2*sizeof(pointer)
> and stored the typmod and/or attlen in it?

The fundamental property of a Datum is that you can pass it by value to
a C function. This generally means it has to fit in a register. On the
whole, the CPU register size is the same as the pointer size, so
2*sizeof(pointer) is unlikely to fit...

Have a nice day,
--
Martijn van Oosterhout   <kleptog@svana.org>   http://svana.org/kleptog/
> From each according to his ability. To each according to his ability to litigate.

pgsql-hackers by date:

Previous
From: Gregory Stark
Date:
Subject: Re: Fixed length data types issue
Next
From: Gevik Babakhani
Date:
Subject: Re: UUID/GUID discussion leading to request for hexstring bytea?