From 515c666b60f7f81f6b2a004ebfb91b358188470c Mon Sep 17 00:00:00 2001 From: Masahiko Sawada Date: Thu, 26 Mar 2026 10:17:23 -0700 Subject: [PATCH v1] doc: Add note about collation requirements for base32hex sortability. While fixing the base32hex UUID sortability test in commit 89210037a0a, it turned out that the expected lexicographical order is only maintained under the C collation (or an equivalent byte-wise collation). Since this is not just a testing quirk but could be a real trap users might fall into when sorting encoded data in their databases, we added a note to the documentation to make this requirement explicitly clear. Reviewed-by: Discussion: https://postgr.es/m/CAD21AoAwX1D6baSGuQXm0mzPXPWB07kgaoaaahjNHHenbdY24A@mail.gmail.com --- doc/src/sgml/func/func-binarystring.sgml | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/doc/src/sgml/func/func-binarystring.sgml b/doc/src/sgml/func/func-binarystring.sgml index 0aaf9bc68f1..9f731d7bca0 100644 --- a/doc/src/sgml/func/func-binarystring.sgml +++ b/doc/src/sgml/func/func-binarystring.sgml @@ -790,6 +790,14 @@ produces a 26-character string compared to the standard 36-character UUID representation. + + + To maintain the lexicographical sort order of the encoded data, + ensure that the text is sorted using the C collation + (e.g., using COLLATE "C"). Natural language + collations may sort characters differently and break the ordering. + + -- 2.53.0