I'm thinking that there isn't any way currently of working out how big a
compressed toast object is?
All existing functions decompress the object before we do anything to
it, AFAICS. Am I missing something?
So there's no way currently of working out how good your compression is
for individual values or when you have multiple toasted columns, other
than writing a new function?
-- Simon Riggs 2ndQuadrant http://www.2ndQuadrant.com