[GENERAL] WAL being written during SELECT * query

[Tom DalPozzo]

Hi,
I have a very big table (10GB).
I noticed that many WAL segments are being written when elaborating read
only transactions like this:
select * from dati25600000000 where id >43000000 limit 1000000;
I don't understand why are there WAL writings during read only transactions.
Regards
Pupillo