On Mon, Dec 18, 2017 at 2:18 AM, Tom Dunstan <pgsql@tomd.cc> wrote:
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>> A timestamptz stores everything as UTC and the value is converted to the session time zone upon retrieval.
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> Which is exactly what we want.
If a random person can interject here, I believe what Tom Dunstan is asking about here is the cheapest way to do a raw conversion of *all* columns in *all* tables with the underlying assumption that the data does not need to be touched at all (as the data representation is the same between timestamp and timestamptz).
Hence he is showing manipulating the pg_attribute and pg_table values.