Re: Testing castability of text to numeric

Hi Folks,

I thought that I would point out that an answer that answers my 
original query (how to test for castability without throwing exception) 
was posted to the pgsql-general list on Sunday, by Joe Conway.  He has 
an "str_validate" set of functions which he makes available at 
joeconway.com.  Thanks to Joe.

Best,

Randall


On Friday, May 16, 2003, at 10:57 AM, Achilleus Mantzios wrote:

> On Fri, 16 May 2003, Christoph Haller wrote:
>
>>>
>>> I am trying to create a function that will test if a given text value
>>> may safely be cast to numeric, returning the numeric cast or null if
>>> impossible.
>
> I think that progress is being made on
> having java as a serverside language
> (i.e. plpgjava).
> Stored procedures in java would be really handy in order
> to do staff like that, java is known for its
> "exceptional" exception handling!
>
> What language do you use to bould your applications??
>
>>>
>>> Is there a way to "catch" the "ERROR:  Bad numeric input format"
>> error?
>>>
>>> I ask that rather than about what the numeric format is for
>> regex-style
>>> testing because if this works I may want to use a similar method to
>>> check if a given text value casts safely to other types, like date.
>>>
>> I don't know of any way to catch errors.
>> And I can't see any way how to test castability via regex. Can you?
>> The only way I can think of at the moment is writing a C function.
>>
>> Regards, Christoph
>>
>>
>>
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>
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> Achilleus Mantzios
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