pgsql: docs: clarify that only INSERT and UPDATE triggers can mod. NEW

docs: clarify that only INSERT and UPDATE triggers can mod. NEW

The point is that DELETE triggers cannot modify any values.

Reported-by: Eugen Konkov

Discussion: /messages/by-id/919823407.20191029175436@yandex.ru

Backpatch-through: 9.4

Branch
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REL9_5_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/b7ee1d345b68b0cecfc3c2f2e2f99ab2c4371964

Modified Files
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doc/src/sgml/trigger.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)