> Tatsuo Ishii <ishii@postgresql.org> writes:
>> While reading planstats.sgml, I encounted a sentence which I don't
>> understand.
>
>> These numbers are current as of the last <command>VACUUM</> or
>> <command>ANALYZE</> on the table. The planner then fetches the
>> actual current number of pages in the table (this is a cheap operation,
>> not requiring a table scan). If that is different from
>> <structfield>relpages</structfield> then
>> <structfield>reltuples</structfield> is scaled accordingly to
>> arrive at a current number-of-rows estimate. In this case the value of
>> <structfield>relpages</structfield> is up-to-date so the rows estimate is
>> the same as <structfield>reltuples</structfield>.
>
>> I don't understand the last sentence (In this case...). For me it
>> seems it is talking about the case when replages is not different from
>> what the planner fetches from the table. If so, why "In this case"?
>
> I think what it meant is "In the example above, ...". Feel free to
> change it if you think that is clearer.
Oh, I see. I'm going to change "In this case" to "In the example above".
Best regards,
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese:http://www.sraoss.co.jp