Re: Fields float4 don't return any row when selecting a

Bruno Wolff III wrote:

> On Tue, Jun 17, 2003 at 23:26:07 -0300,
> "Francisco Figueiredo Jr." <fxjrlists(at)yahoo(dot)com(dot)br> wrote:
>
>>
>>Hi all,
>>I'm using the 7.4 cvs version on cygwin and I noticed that if I have a
>>table with a field of float4 type and try to do a simple select:
>>select * from table where field_float4 = 4.4
>>
>>it doesn't return any rows.
>>In the same table I have a float8 field and it works ok.
>>
>>If I try with a value without the . in the float4 field it also works.
>
>
> I believe that is because the constant 4.4 is originally a float 8 value
> and the comparison to the float4 value is done by promoting to float8.
> And the nearest float4 value to 4.4 is not the same as the nearest
> float8 value to 4.4. I think both quoting the 4.4 or casting it to
> float4 will solve your problem.
>

> Note that under many circumstances equality tests between floating
> values doesn't make a lot of sense. If you really want to do this,
> you might want to consider using the numeric type.
>

Thanks!! I will use the quoting, as it could be used with both float4
and float8 values.

--
Regards,
Francisco Figueiredo Jr.
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