Gregory Stark <[EMAIL PROTECTED]> writes: > ... it's kind > of pie-in-the-sky since it depends on every column being toasted (and not > compressed). It's much more normal to have some columns be quite large and > others more normal sized or different data types.
Yeah. I think those numbers should simply be removed from the discussion entirely, because they are bogus. There is no real-world situation where someone is going to put 1Gb into each and every field of a row. The limits that should be stated are 1Gb per column and 250-1600 columns per table --- let the readers draw their own conclusions from those. As Greg notes, the 400-column figure came from presuming that every column gets toasted out-of-line; but that's not totally realistic either. Furthermore, we have some untoastable types that are wider than a toast pointer. The worst case seems to be 32 bytes for box, line, and lseg (I ignore "name" which is stated not to be intended for general-purpose use). If you made a table of only "box" columns you could get at most a bit over 250 of them on a standard-size page. So I think that's what we should quote as the lower bound. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings