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Date: Mon, 10 Apr 2017 18:00:50 +0200
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Subject: Re: [PHP-DEV] [RFC] PDO Float Type
From: php@beccati.com (Matteo Beccati)

Hi Adam,

On 10/04/2017 17:42, Adam Baratz wrote:
> Just so I understand your concern, it's that fixed-precision types are
> meaningfully different and there could be clashes with other types of
> floats? I agree with you on that, but I'm not sure what the right
> solution is. There isn't a C type for fixed-precision floats, or even a
> PHP type. How would the flow of data work so nothing's lost/altered
> along the way? My general thought would be that if fixed-precision
> matters, then you should be storing values as strings, that there'd be a
> whole other set of pitfalls opened up with a PDO::PARAM_NUMERIC type.
> 
> I realize this is all downsides, which isn't the most constructive way
> to respond. Happy to talk through details if you have specific
> suggestions for how this type would work in practice.

My concern is that numeric/decimal types should be treated/sent as
strings (and eventually dealt with using e.g. bcmath) and not converted
to floats, unless one seeks trouble and loves rounding errors, while the
new PDO::PARAM_FLOAT const could instead be seen as a good fit to many
unexperienced (and some experienced) people.

Hence my suggestion of a PDO::PARAM_NUMERIC const that could in fact
just be an alias for PDO::PARAM_STR for most of the drivers.

The most important thing to me is to discourage the misuse of
PDO::PARAM_FLOAT for types that are not actually floating points.


Cheers
-- 
Matteo Beccati

Development & Consulting - http://www.beccati.com/