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Subject: Re: [PHP-DEV] PDO::PARAM_DOUBLE
From: php@beccati.com (Matteo Beccati)

Hi Adam,

On 07/12/2016 23:37, Adam Baratz wrote:
>     For decimal, double wouldn't be the correct type anyway, as it could
>     cause loss of precision.
> 
> 
> Sure, agree the name is imprecise. "Double" is mainly relevant to zvals.

It's not about naming. Double is relevant both to PHP and SQL and is a
floating point type. On the other hand, decimal/numeric fields should be
represented as strings as they are fixed point/precision, which is
something we don't have in stock php. In fact bcmath uses strings too.

>     > Is there a reason PDO::PARAM_DOUBLE doesn't exist?
> 
>     I don't know if there's am historical reason. I think it should be
>     there, but to be honest, I'm not sure it's worth the effort at this
>     point.
> 
> 
> Say more on why you don't think there'd be a payoff? I'd think that it
> would be worth taking the (I'm guessing) max. 3 days involved to add
> missing functionality to a widely-used extension.

I think it would be the biggest PDO API change to date and we should be
very careful. Lots of #ifdefs for pecl pdo_* developers to add, if they
want to keep their extensions backwards compatible.

My biggest worry is its potential misuse for decimal fields. I know this
isn't reason enough for denying an improvement, but there are already
too many people mistakenly using double for currency data and monetary
calculations...

That said, I think this more than anything else requires a proper RFC
and discussion.


Cheers
-- 
Matteo Beccati

Development & Consulting - http://www.beccati.com/