From: Tom Lane <tgl@sss.pgh.pa.us>
To: Wells Oliver <wells.oliver@gmail.com>
cc: pgsql-admin <pgsql-admin@postgresql.org>
Subject: Re: Casting json (or jsonb) to real
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Comments: In-reply-to Wells Oliver <wells.oliver@gmail.com>
	message dated "Tue, 31 May 2022 18:08:54 -0700"
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Date: Tue, 31 May 2022 21:18:18 -0400
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Wells Oliver <wells.oliver@gmail.com> writes:
> Well, it's because the representation of the value is getting double
> quoted, so it's
> select '"1.453"'::real, which yields ERROR:  cannot cast jsonb string to
> type real.

Oh ... that perhaps wasn't a great choice.  But it looks like you could
pretend the jsonb is a 1-element array, and do

regression=# select ('"1.4531"'::jsonb->>0)::real;
 float4 
--------
 1.4531
(1 row)

			regards, tom lane