Proposal to improve uniq function documentation in intarray extension
The following documentation comment has been logged on the website:
Page: https://www.postgresql.org/docs/14/intarray.html
Description:
The **uniq** function in the **intarray** extension removes **adjacent**
duplicates from an integer array. The documentation[0]https://www.postgresql.org/docs/current/intarray.html#INTARRAY-FUNC-TABLE about this behavior
is correct, but the example is a bit misleading, because it sorts the array
before applying uniq. The sort can be overlooked **easily** and leads to the
impression that **uniq** removes all duplicates from the array.
I propse to change the example to somthing like that:
uniq('{1,2,2,3,1,1}'::integer[]) → {1,2,3,1}
It might be a good idea to refer to the **sort** function in case one wants
to remove all duplicates.
Cheers, Martin Kalcher
[0]: https://www.postgresql.org/docs/current/intarray.html#INTARRAY-FUNC-TABLE
https://www.postgresql.org/docs/current/intarray.html#INTARRAY-FUNC-TABLE
PG Doc comments form <noreply@postgresql.org> writes:
The **uniq** function in the **intarray** extension removes **adjacent**
duplicates from an integer array. The documentation[0] about this behavior
is correct, but the example is a bit misleading, because it sorts the array
before applying uniq. The sort can be overlooked **easily** and leads to the
impression that **uniq** removes all duplicates from the array.
I propse to change the example to somthing like that:
uniq('{1,2,2,3,1,1}'::integer[]) → {1,2,3,1}
You have a point, but the example of use with sort() is pretty useful in
its own right, particularly for people for whom "blah blah | sort | uniq"
is not second nature. Fortunately, there's no longer any reason we have
to limit ourselves to one example. I propose this:
diff --git a/doc/src/sgml/intarray.sgml b/doc/src/sgml/intarray.sgml
index f930c08eeb..18c6f8c3ba 100644
--- a/doc/src/sgml/intarray.sgml
+++ b/doc/src/sgml/intarray.sgml
@@ -131,6 +131,11 @@
</para>
<para>
Removes adjacent duplicates.
+ Often used with <function>sort</function> to remove all duplicates.
+ </para>
+ <para>
+ <literal>uniq('{1,2,2,3,1,1}'::integer[])</literal>
+ <returnvalue>{1,2,3,1}</returnvalue>
</para>
<para>
<literal>uniq(sort('{1,2,3,2,1}'::integer[]))</literal>regards, tom lane
On 3 Jun 2022, at 17:34, Tom Lane <tgl@sss.pgh.pa.us> wrote:
.. there's no longer any reason we have
to limit ourselves to one example. I propose this:diff --git a/doc/src/sgml/intarray.sgml b/doc/src/sgml/intarray.sgml index f930c08eeb..18c6f8c3ba 100644 --- a/doc/src/sgml/intarray.sgml +++ b/doc/src/sgml/intarray.sgml @@ -131,6 +131,11 @@ </para> <para> Removes adjacent duplicates. + Often used with <function>sort</function> to remove all duplicates. + </para> + <para> + <literal>uniq('{1,2,2,3,1,1}'::integer[])</literal> + <returnvalue>{1,2,3,1}</returnvalue> </para> <para> <literal>uniq(sort('{1,2,3,2,1}'::integer[]))</literal>
+1
--
Daniel Gustafsson https://vmware.com/
Daniel Gustafsson <daniel@yesql.se> writes:
On 3 Jun 2022, at 17:34, Tom Lane <tgl@sss.pgh.pa.us> wrote:
.. there's no longer any reason we have
to limit ourselves to one example. I propose this:
+1
Done like that, then.
regards, tom lane
Thank you very much. The new documentation is way better.
Am 03.06.22 um 19:55 schrieb Tom Lane:
Show quoted text
Daniel Gustafsson <daniel@yesql.se> writes:
On 3 Jun 2022, at 17:34, Tom Lane <tgl@sss.pgh.pa.us> wrote:
.. there's no longer any reason we have
to limit ourselves to one example. I propose this:+1
Done like that, then.
regards, tom lane