Bruce Momjian <pgman@candle.pha.pa.us> writes:
> Manfred Koizar wrote:
>> This 1600 column limit has nothing to do with block size. It is
>> caused by the fact that a heap tuple header cannot be larger than 255
>> bytes, so there is a limited number of bits in the null bitmap.
> Are you sure. Then our max would be:
> 255 * 8 = 2040
I assure you, Manfred knows heap tuple headers inside and out ;-)
See the comments at the top of src/include/access/htup.h.
regards, tom lane