Wells Oliver <wells(dot)oliver(at)gmail(dot)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