土卜皿 <pengcz.nwpu@gmail.com> writes: > for studying polyphase merge algorithm of tuplesort.c, I use ddd and > apend a table, which has a schema as follows:
> ...
> and has 36684 records, and every record is like: > id code article name department > 31800 266 \N Machault 77
> and for getting into external sort, I type the following command:
> select * from towns order by name desc;
> but I found it need not reach D5 and D6 during sorting,
That doesn't sound like enough data to force it to spill to disk at all; at least not unless you turn down work_mem to some very small value.
hi, Tom
thanks a lot!
work_mem you said remind me one more thing I did, I tried to change BLCKSZ = 8192/2, and successfully compiled, but I got a error when executing initdb
