Obsolete comment in commands/analyze.c
Hi,
I think commit 83e176ec1, which moved block sampling functions to
utils/misc/sampling.c, forgot to update this comment in
commands/analyze.c: "This algorithm is from Jeff Vitter's paper (see
full citation below)"; since the citation was also moved to
utils/misc/sampling.c, I think the "see full citation below" part
should be updated accordingly. Attached is a patch for that.
Best regards,
Etsuro Fujita
Attachments:
update-comment.patchapplication/octet-stream; name=update-comment.patchDownload
diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c
index 6cb545c126..d7004e5313 100644
--- a/src/backend/commands/analyze.c
+++ b/src/backend/commands/analyze.c
@@ -1048,13 +1048,13 @@ acquire_sample_rows(Relation onerel, int elevel,
* The first targrows sample rows are simply copied into the
* reservoir. Then we start replacing tuples in the sample until
* we reach the end of the relation. This algorithm is from Jeff
- * Vitter's paper (see full citation below). It works by
- * repeatedly computing the number of tuples to skip before
- * selecting a tuple, which replaces a randomly chosen element of
- * the reservoir (current set of tuples). At all times the
- * reservoir is a true random sample of the tuples we've passed
- * over so far, so when we fall off the end of the relation we're
- * done.
+ * Vitter's paper (see full citation in utils/misc/sampling.c). It
+ * works by repeatedly computing the number of tuples to skip
+ * before selecting a tuple, which replaces a randomly chosen
+ * element of the reservoir (current set of tuples). At all times
+ * the reservoir is a true random sample of the tuples we've
+ * passed over so far, so when we fall off the end of the relation
+ * we're done.
*/
if (numrows < targrows)
rows[numrows++] = ExecCopySlotHeapTuple(slot);
On 27 Jun 2019, at 13:05, Etsuro Fujita <etsuro.fujita@gmail.com> wrote:
since the citation was also moved to
utils/misc/sampling.c, I think the "see full citation below" part
should be updated accordingly. Attached is a patch for that.
Agreed, nice catch!
cheers ./daniel
On Thu, Jun 27, 2019 at 01:53:52PM +0200, Daniel Gustafsson wrote:
On 27 Jun 2019, at 13:05, Etsuro Fujita <etsuro.fujita@gmail.com> wrote:
since the citation was also moved to
utils/misc/sampling.c, I think the "see full citation below" part
should be updated accordingly. Attached is a patch for that.Agreed, nice catch!
Thanks, committed.
cheers
--
Tomas Vondra http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
On Fri, Jun 28, 2019 at 1:02 AM Tomas Vondra
<tomas.vondra@2ndquadrant.com> wrote:
On Thu, Jun 27, 2019 at 01:53:52PM +0200, Daniel Gustafsson wrote:
On 27 Jun 2019, at 13:05, Etsuro Fujita <etsuro.fujita@gmail.com> wrote:
since the citation was also moved to
utils/misc/sampling.c, I think the "see full citation below" part
should be updated accordingly. Attached is a patch for that.Agreed, nice catch!
Thanks, committed.
Thanks for committing, Tomas! Thanks for reviewing, Daniel!
Best regards,
Etsuro Fujita