Simon Riggs wrote:
>
> That sounds more like what I was after.
>
> So let me check my understanding: For TOASTed data pg_column_size()
> tells you how many bytes the column value occupies when decompressed. So
> there isn't any way of finding out how many bytes a column value
> actually occupies when it is both compressed and external?
>
>
I dimly recall getting confused by this when writing this guy:
From what I can see: pg_column_size calls toast_datum_size for any
variable length attribute - and then gets the external pointer and
returns its va_extsize component (which looks to me like the
*compressed* size.)
Cheers
Mark