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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andreas Karlsson <andreas@proxel.se>
cc: Andrei Klychkov <andrew.a.klychkov@gmail.com>,
        Jim Jones <jim.jones@uni-muenster.de>,
        Fujii Masao <masao.fujii@gmail.com>,
        pgsql-hackers@lists.postgresql.org
Subject: Re: [PATCH] Fix ALTER SYSTEM empty string bug for GUC_LIST_QUOTE
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Comments: In-reply-to Andreas Karlsson <andreas@proxel.se>
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Andreas Karlsson <andreas@proxel.se> writes:
> Honestly none of the alternatives is very appealing and v6 is probably 
> the least bad.

Yeah, that's about where I'm at with this.

> When I ran into this issue I thought about adding and EMPTY keyword (we 
> do not want more keywords) or adding support for specifying array 
> literals like this [] or [a, b], but that would be confusing since 
> postgresql.conf does not allow any such syntax.

I would have preferred a different keyword.  But AFAICS it'd have to
be a fully-reserved word, and creating a new one of those has to
clear a pretty high bar.  NULL is not so far off...

			regards, tom lane