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From: Tom Lane <tgl@sss.pgh.pa.us>
To: "James Pang (chaolpan)" <chaolpan@cisco.com>
cc: "pgsql-admin@lists.postgresql.org" <pgsql-admin@lists.postgresql.org>
Subject: Re: inserts bypass encoding conversion
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Comments: In-reply-to "James Pang (chaolpan)" <chaolpan@cisco.com>
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"James Pang (chaolpan)" <chaolpan@cisco.com> writes:
>   In this case, the real value stored in database is UTF8 byte sequence
>   instead of LATIN1 encoding text, right?

Not if you have server_encoding = LATIN1, as you stated earlier.
In that case, the data in the database is in LATIN1, and chr()
interprets its argument as a LATIN1 code value --- which happens
to look enough like a Unicode code point to be possibly confusing,
until you try to use code points that aren't within LATIN1.

			regards, tom lane