pgsql: doc: mention that to_char() values are rounded

doc: mention that to_char() values are rounded

Reported-by: barsikdacat@gmail.com

Diagnosed-by: Laurenz Albe

Discussion: /messages/by-id/168991536429.626.9957835774751337210@wrigleys.postgresql.org

Author: Laurenz Albe

Backpatch-through: 11

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/18aecf5e15a6d6fb655a6db9041147704cd0b9cf

Modified Files
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doc/src/sgml/func.sgml | 8 ++++++++
1 file changed, 8 insertions(+)