> Source instance: PostgreSQL 13.7 on RHEL 7.9 > Target instance PostgreSQL 13.7 on RHEL 8.7
glibc on those 2 versions of RHEL have very different ideas of what the sort order should be. Try running the following and you'll likely see different results on RHEL 7.9 vs 8.7
CREATE TABLE t1 (c1 varchar PRIMARY KEY); INSERT INTO t1 VALUES ('1-a'), ('1a'), ('1-aa'); SELECT * FROM t1 ORDER BY c1;