Обсуждение: pgsql: Make psql's "\pset format" command reject non-uniqueabbreviatio

Make psql's "\pset format" command reject non-unique abbreviations.

The previous behavior of preferring the oldest match had the advantage
of not breaking existing scripts when we add a conflicting format name;
but that behavior was undocumented and fragile (it seems just luck that
commit add9182e5 didn't break it).  Let's go over to the less mistake-
prone approach of complaining when there are multiple matches.

Since this is a small compatibility break, no back-patch.

Daniel Vérité

Discussion: https://postgr.es/m/cb7e1caf-3ea6-450d-af28-f524903a030c@manitou-mail.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/eaf746a5b85a6a794e659f0954cf0015e42213f4

Modified Files
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src/bin/psql/command.c | 59 +++++++++++++++++++++++++++++++++++---------------
1 file changed, 41 insertions(+), 18 deletions(-)