From: "Josh Berkus" <josh@agliodbs.com>
Subject: Re: Request for builtin function: Double_quote 
To: Tom Lane <tgl@sss.pgh.pa.us>, josh@agliodbs.com
Cc: pgsql-sql@postgresql.org, pgsql-hackers@postgresql.org
Date: Tue, 18 Jun 2002 08:49:33 -0700
Message-ID: <web-1531608@davinci.ethosmedia.com>
In-Reply-To: <26287.1024411733@sss.pgh.pa.us>
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Chris, Tom:

Yes, thank you Chris, I meant a builtin SQL function.

> > Given the amount of qoute nesting we do in Postgres, I thought that
> we need a 
> > function that handles automatic doubling of quotes within strings.
>   I've 
> > written one in PL/pgSQL (below).  I'd really love to see this
> turned into a 
> > builtin C function.
> 
> What does this do that isn't already done by quote_literal?

Well, first off, quote_literal isn't in the documentation under
"Functions and Operators".    So this is the first I've heard about it
-- or probably anyone else outside the core team.   How long has it
been around?

Second, double_quote does not return the outside quotes, just the
inside ones ... it's for passing string values to EXECUTE statements.
  However, now that I know that quote_literal exists, I can simplify
the double_quote statement considerably.  

Therefore, I withdraw my initial request, and request instead that
quote_literal be added to the function documentation in String
Functions and Operators.

I will event supply text for the functions table:

function			returns		
quote_literal(string text)	text		

explain
Returns the entire string passed to it, including quote marks.  Useful
for nesting quotes, such as in the EXECUTEing dynamic queries.

example			result
quote_literal('O''Reilly')	'O''Reilly'


-Josh Berkus

-Josh Berkus