Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> Neil Conway wrote:
>> Is there a reason why the reltuples column of pg_class is stored as a
>> "real", rather than one of the integer data types?
> That is an excellent question. I assume it is related to having > 4
> billion rows, but we have int8 for that.
1. We support tables > 4G rows.
2. int8 is not available on all platforms.
3. The only use for reltuples is in the optimizer, which is perfectly
content with approximate values.
regards, tom lane