Re: problem about maximum row size ?

zhaoxin <zhaox@necas.nec.com.cn> writes:
> I have a question about maximum row size .
> In pgsql FAQ, I can find this description :
>   ...
>   Maximum size for a row? 1.6TB
>   ...

> does it mean 1600 text column in a table and 1G every column ?

> but, when I test this case by psqlodbc, I got some error :

This was posted in a fairly randomly chosen list, but I think it does
expose an error in the FAQ: you can't fit 1600 TOAST pointers into one
row and so the 1.6TB figure is overoptimistic.

Since TOAST pointers are 20 bytes, a reasonable number for the maximum
number of large toasted fields is about 400, which would make the
correct entry for this question 400Gb.  This could be improved by using
a non-default block size, so this should be listed as one of the limits
affected by block size.

            regards, tom lane