date + interval year - why is the return type convered to a timestamp? - Mailing list pgsql-sql

From the6campbells
Subject date + interval year - why is the return type convered to a timestamp?
Date
Msg-id 22431f1b0910221404i52040b19s7c89f6dda4ae187d@mail.gmail.com
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Responses Re: date + interval year - why is the return type convered to a timestamp?  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-sql
Why is Postgres returning a timestamp instead of the expected date data type for the first expression (the second returns a date)? 

In other words, is this a known bug or is it design intent. The manuals did not seem to appear to say this is intentional behaviour but is not SQL standard.

select date '2001-03-30' - interval '1' year, date '2001-03-30' - integer '365' from tversion



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