About syntax: i vote for current syntax "reindex table CONCURRENTLY tablename". This looks consistent with existed CREATE INDEX CONCURRENTLY and REFRESH MATERIALIZED VIEW CONCURRENTLY.
regards, Sergei [1]: https://www.postgresql.org/message-id/CAB7nPqT%2B6igqbUb59y04NEgHoBeUGYteuUr89AKnLTFNdB8Hyw%40mail.gmail.com
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