Documentation error in tutorial page for Window Functions

Started by PG Bug reporting formover 1 year ago3 messagesdocs
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#1PG Bug reporting form
noreply@postgresql.org

The following documentation comment has been logged on the website:

Page: https://www.postgresql.org/docs/17/tutorial-window.html
Description:

In Section 3.5 Window Functions, the sentence that currently says:
"As shown here, the rank function produces a numerical rank for each
distinct ORDER BY value in the current row's partition..."

should say:
"As shown here, the rank function produces a numerical rank for each
distinct depname value in the current row's partition..."

https://www.postgresql.org/docs/current/tutorial-window.html

Thanks for the otherwise great tutorial.

#2David G. Johnston
david.g.johnston@gmail.com
In reply to: PG Bug reporting form (#1)
Re: Documentation error in tutorial page for Window Functions

On Sunday, November 10, 2024, PG Doc comments form <noreply@postgresql.org>
wrote:

The following documentation comment has been logged on the website:

Page: https://www.postgresql.org/docs/17/tutorial-window.html
Description:

In Section 3.5 Window Functions, the sentence that currently says:
"As shown here, the rank function produces a numerical rank for each
distinct ORDER BY value in the current row's partition..."

should say:
"As shown here, the rank function produces a numerical rank for each
distinct depname value in the current row's partition..."

https://www.postgresql.org/docs/current/tutorial-window.html

If we wanted to name the relevant column it would be salary, not depname.
It is the column(s) in the order by that matter here. Or I suppose the
combination of depname and salary. Though it was already covered that each
partition resets all aggregates. Here we are not talking about reset but
when something increments.

David J.

#3Scott Preschern
shineondarkside@gmail.com
In reply to: David G. Johnston (#2)
Re: Documentation error in tutorial page for Window Functions

Thanks, I see now. Then I'll suggest this clarification instead:

"The rank function produces a numerical rank for each distinct value in the
ORDER BY clause within the current row's partition. In this example, ranks
are incremented in order of salary within each partition of depname. If the
ORDER BY clause refers to multiple columns, the rank is incremented at each
unique combination of those columns. rank needs no explicit parameter,
because its behavior is entirely determined by the OVER clause."

Scott

On Mon, Nov 11, 2024 at 5:39 AM David G. Johnston <
david.g.johnston@gmail.com> wrote:

Show quoted text

On Sunday, November 10, 2024, PG Doc comments form <noreply@postgresql.org>
wrote:

The following documentation comment has been logged on the website:

Page: https://www.postgresql.org/docs/17/tutorial-window.html
Description:

In Section 3.5 Window Functions, the sentence that currently says:
"As shown here, the rank function produces a numerical rank for each
distinct ORDER BY value in the current row's partition..."

should say:
"As shown here, the rank function produces a numerical rank for each
distinct depname value in the current row's partition..."

https://www.postgresql.org/docs/current/tutorial-window.html

If we wanted to name the relevant column it would be salary, not depname.
It is the column(s) in the order by that matter here. Or I suppose the
combination of depname and salary. Though it was already covered that each
partition resets all aggregates. Here we are not talking about reset but
when something increments.

David J.