Re: finding changed blocks using WAL scanning

On Sat, Apr 20, 2019 at 5:54 PM Bruce Momjian <bruce@momjian.us> wrote:
> Good point.  You mentioned:
>
>         It seems better to me to give the files names like
>         ${TLI}.${STARTLSN}.${ENDLSN}.modblock, e.g.
>         00000001.0000000168000058.00000001687DBBB8.modblock, so that you can
>         see exactly which *records* are covered by that segment.
>
> but it seems like it should be ${TLI}.${ENDLSN}... (END first) because
> you would not want to delete the modblock file until you are about to
> delete the final WAL, not the first WAL, but as you mentioned, it might
> be ENDLSN-1.

Hmm.  It seems to me that it is almost universally the convention to
put the starting point prior to the ending point.  If you are taking a
biology class, the teacher will not tell you to study chapters six
through three.

-- 
Robert Haas
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