On Mon, Oct 28, 2013 at 11:12 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> The idea I'm thinking about at the moment is that toast tokens of this
> sort might each contain a function pointer to the required flattening
> function. This avoids an expensive catalog lookup when flattening is
> needed. We'd never accept such a thing for data destined for disk;
> but since the whole point here is that such data lives only in memory,
> I can't see anything wrong with including a function pointer in it.
This might be OK, but it bloats the in-memory representation. For
small data types like numeric that might well be significant.
--
Robert Haas
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