Обсуждение: pgsql: doc: PG 12 relnotes, add mention of single-child optimization

doc:  PG 12 relnotes, add mention of single-child optimization

Add mention of single-child optimization for partitions and UNION ALL.

Reported-by: David Rowley

Discussion: https://postgr.es/m/CAKJS1f8R8riwBXw==7ijV=UZNuhP+3qXgDBKSiM+=_cTf4mXXw@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b9a0724cf7a3ecf19aaaa098ffd26e52bb800c5c

Modified Files
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doc/src/sgml/release-12.sgml | 12 ++++++++++++
1 file changed, 12 insertions(+)