Re: Cast to integer

A. Kretschmer wrote:

>am  05.10.2005, um 15:08:33 +0200 mailte Robert Osowiecki folgendes:
>
>
>>Hello!
>>
>>Anyone could explain to me, why cast(3.33 to int) works (from float, I
>>suppose)  but cast('3.33' to int) (from text) does not? And what if I
>>create a cast for that: is it possibly dangerous?
>>
>>
>
>test=# select '3.33'::float::int;
> int4
>------
>    3
>(1 row)
>
>
>
Let me explain better. I encountered this problem when I tried to write
general unit-calculation (from kilograms to punds, for example) function
operating on any arithmetic datatype: with float and numeric it went all
ok, but failed with integer on "return $result" with error "invalid
input syntax for integer". My function internally operated on numeric
type. I wrote a wrap-around for integer, because I've been afraid, that
changing "text to integer" cast (or input function, whatever it is)
could damage something important.

R.