Re: string functions and operators

From: Petru Ghita <petrutz@venaver.info>
To: Neil Stlyz <neilstylz@yahoo.com>; pgsql-sql mailing list <pgsql-sql@postgresql.org>
Sent: Mon, March 22, 2010 8:08:30 PM
Subject: Re: [SQL] string functions and operators

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For numeric data types use:

http://www.postgresql.org/docs/8.4/static/functions-math.html

You could then use|floor|(dp or numeric)|| for example:

postgres=# select floor(71.912);
 floor
- -------
    71
(1 row)

postgres=# select 71.912-floor(71.912);
 ?column?
- ----------
    0.912


But as you might have negative numbers in there I guess you should
abs() the values like in:

postgres=# select abs(71.912)-floor(abs(71.912));
 ?column?
- ----------
    0.912


postgres=# select abs(-171.912)-floor(abs(-171.912));
 ?column?
- ----------
    0.912
(1 row)






On 23/03/2010 2:50, Petru Ghita wrote:
> That field of yours... what type is it? Is it TEXT? is it a numeric
> type? If it's TEXT, why don't you make it say... NUMERIC(/10/,
> /6///)?
>
> http://www.postgresql.org/docs/8.4/interactive/datatype-numeric.html#DATATYPE-NUMERIC-DECIMAL
>
>
>
>
On 23/03/2010 2:20, Neil Stlyz wrote:
>> Hello,
>
>
>
>> I have a dilema and I was hoping someone here may offer guidance
>
>> or assistance. I bet this is a very simple question for

 someone
>
>> out there but I am having problems coming up with a solution.
> Here
>
>> it is...
>
>
>
>> suppose I have a field with the following values:
>
>
>
>> 77.1 77.2 134.1 134.2 134.3 5.1 5.2
>
>
>
>> I need two seperate SELECT queries. One would return the
> following
>
>> values (everything left of the decimal point)
>
>
>
>> 77 77 134 134 5 5
>
>
>
>> The second query would return all of the values to the right of
>
>> the decimal point:
>
>
>
>> 1 2 1 2 3 1 2
>
>
>
>
>
>> Now, I have been using the following information (although very
>
>> Greek) to try to solve this problem:
>
>
>
>
>

 http://www.postgresql.org/docs/current/static/functions-string.html
>
>
>
>
>  And I have been playing around with the syntax of the following:
>
>
>
>> substring('112.5' from '%#"___.#"_' for '#')
>
>
>
>> but the aforementioned is not quite working out... can someone
>
>> please show me a string function that will produce the desired
>
>> results?
>
>
>
>> Thanks! ~n
>
>
>
>
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