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	Fri, 5 Oct 2018 17:32:47 -0400
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Konstantin Knizhnik <k.knizhnik@postgrespro.ru>
cc: PostgreSQL Hackers <pgsql-hackers@postgresql.org>,
        Robert Haas <robertmhaas@gmail.com>
Subject: Re: now() vs transaction_timestamp()
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Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
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I wrote:
> So transaction_timestamp() is definitely buggy, but we're not out of the
> woods yet: SQLValueFunction is treated as parallel-safe, but it also has
> some instances that are equivalent to transaction_timestamp and so do not
> work correctly.

Oh, and I notice that timestamp_in and related functions are marked
parallel safe, which is equally broken since the conversion of 'now'
also depends on xactStartTimestamp.

			regards, tom lane