From a64f3f64a9f04c1f5da9a51fe760c40480585fd4 Mon Sep 17 00:00:00 2001 From: Masahiko Sawada Date: Wed, 25 Mar 2026 18:07:11 -0700 Subject: [PATCH] Fix UUID sortability tests in base32hex encoding. The recently added test for base32hex encoding of UUIDs failed on buildfarm member hippopotamus using natural language locales (such as cs_CZ). This happened because those collations may sort characters differently, which breaks the strict byte-wise lexicographical ordering expected by base32hex encoding. This commit fixes the regression tests by explicitly using the C collation. Additionally, add a note to the documentation to warm users that they must use the C collation if they want to maintain the lexicographical sort order of the encoded data. Per buildfarm member hippopotamus. Analyzed-by: Tom Lane Discussion: https://postgr.es/m/682417.1774482047@sss.pgh.pa.us --- doc/src/sgml/func/func-binarystring.sgml | 9 +++++++++ src/test/regress/expected/uuid.out | 7 +++++-- src/test/regress/sql/uuid.sql | 7 +++++-- 3 files changed, 19 insertions(+), 4 deletions(-) diff --git a/doc/src/sgml/func/func-binarystring.sgml b/doc/src/sgml/func/func-binarystring.sgml index 0aaf9bc68f1..2ad2cdbea82 100644 --- a/doc/src/sgml/func/func-binarystring.sgml +++ b/doc/src/sgml/func/func-binarystring.sgml @@ -790,6 +790,15 @@ 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. + + diff --git a/src/test/regress/expected/uuid.out b/src/test/regress/expected/uuid.out index 142c529e693..9c5dda9e9ab 100644 --- a/src/test/regress/expected/uuid.out +++ b/src/test/regress/expected/uuid.out @@ -236,8 +236,11 @@ SELECT array_agg(id ORDER BY guid_field) FROM guid3; {1,2,3,4,5,6,7,8,9,10,11,12} (1 row) --- make sure base32hex encoding works with UUIDs and preserves ordering -SELECT array_agg(id ORDER BY guid_encoded) FROM guid3; +-- Test base32hex encoding of UUIDs and its lexicographical sorting property. +-- COLLATE "C" is required to prevent buildfarm failures in non-C locales +-- where natural language collations (such as cs_CZ) would break strict +-- byte-wise ordering. +SELECT array_agg(id ORDER BY guid_encoded COLLATE "C") FROM guid3; array_agg ------------------------------ {1,2,3,4,5,6,7,8,9,10,11,12} diff --git a/src/test/regress/sql/uuid.sql b/src/test/regress/sql/uuid.sql index f2ff00f5ddd..8cc2ad40614 100644 --- a/src/test/regress/sql/uuid.sql +++ b/src/test/regress/sql/uuid.sql @@ -122,8 +122,11 @@ INSERT INTO guid3 (guid_field) SELECT uuidv7() FROM generate_series(1, 10); INSERT INTO guid3 (guid_field) VALUES ('ffffffff-ffff-ffff-ffff-ffffffffffff'::uuid); SELECT array_agg(id ORDER BY guid_field) FROM guid3; --- make sure base32hex encoding works with UUIDs and preserves ordering -SELECT array_agg(id ORDER BY guid_encoded) FROM guid3; +-- Test base32hex encoding of UUIDs and its lexicographical sorting property. +-- COLLATE "C" is required to prevent buildfarm failures in non-C locales +-- where natural language collations (such as cs_CZ) would break strict +-- byte-wise ordering. +SELECT array_agg(id ORDER BY guid_encoded COLLATE "C") FROM guid3; -- Check the timestamp offsets for v7. -- -- 2.53.0