pgsql: doc: Mention that partitions_{done,total} is 0 for REINDEX progr

doc: Mention that partitions_{done,total} is 0 for REINDEX progress reports

REINDEX has recently gained support for partitions, so it can be
confusing to see those fields not being set. Making useful reports for
for such relations is more complicated than it looks with the current
set of columns available in pg_stat_progress_create_index, and this
touches equally REINDEX DATABASE/SYSTEM/SCHEMA. This commit documents
that those two columns are not touched during a REINDEX.

Reported-by: Justin Pryzby
Discussion: https://postgr.es/m/20210216064214.GI28165@telsasoft.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/17661188336c8cbb1783808912096932c57893a3

Modified Files
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doc/src/sgml/monitoring.sgml | 2 ++
1 file changed, 2 insertions(+)