pgsql: doc: Add note about generated columns in foreign tables

doc: Add note about generated columns in foreign tables

Explain that it is not enforced that querying a generated column
returns data that is consistent with the data that was stored.  This
is similar to the note about constraints nearby.

Reported-by: Amit Langote <amitlangote09@gmail.com>

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/348f57ce5be96190491e2153abb47060884f8ebf

Modified Files
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doc/src/sgml/ref/create_foreign_table.sgml | 10 ++++++++++
1 file changed, 10 insertions(+)