Обсуждение: pgsql: Fix some grammar and typos in comments and docs

Fix some grammar and typos in comments and docs

The documentation fixes are backpatched down to where they apply.

Author: Justin Pryzby
Discussion: https://postgr.es/m/20201031020801.GD3080@telsasoft.com
Backpatch-through: 9.6

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/c7f41b2999c3c68899c591d8789bd273f9a61343

Modified Files
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doc/src/sgml/ddl.sgml           | 2 +-
doc/src/sgml/ref/pg_rewind.sgml | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)