Richard van der Hoff <richard@xxxxxxxxxx> writes: > On 16/01/2020 17:12, Magnus Hagander wrote: >> See https://wiki.postgresql.org/wiki/Locale_data_changes for hints on >> which linux distros updated when. > It seems like a plausible explanation but it's worth noting that all the > indexed data here is (despite being in text columns), plain ascii. I'm > surprised that a change in collation rules would change the sorting of > such strings, and hence that it could lead to this problem. Am I naive? Unfortunately, strings containing punctuation do sort differently after these changes, even with all-ASCII data. The example given on that wiki page demonstrates this. RHEL6 (old glibc): $ ( echo "1-1"; echo "11" ) | LC_COLLATE=en_US.utf8 sort 11 1-1 Fedora 30 (new glibc): $ ( echo "1-1"; echo "11" ) | LC_COLLATE=en_US.utf8 sort 1-1 11 I concur with Daniel's suggestion that maybe "C" locale is the thing to use for this data. regards, tom lane
